google styled doc

mail_intake/__init__.py

@@ -1,6 +1,10 @@
 """
 Mail Intake — provider-agnostic, read-only email ingestion framework.
 
+---
+
+## Summary
+
 Mail Intake is a **contract-first library** designed to ingest, parse, and
 normalize email data from external providers (such as Gmail) into clean,
 provider-agnostic domain models.
@@ -20,9 +24,9 @@ as a first-class module at the package root:
 The package root acts as a **namespace**, not a facade. Consumers are
 expected to import functionality explicitly from the appropriate module.
 
-----------------------------------------------------------------------
+---
-Installation
+
-----------------------------------------------------------------------
+## Installation
 
 Install using pip:
 
@@ -35,9 +39,9 @@ Or with Poetry:
 Mail Intake is pure Python and has no runtime dependencies beyond those
 required by the selected provider (for example, Google APIs for Gmail).
 
-----------------------------------------------------------------------
+---
-Basic Usage
+
-----------------------------------------------------------------------
+## Quick start
 
 Minimal Gmail ingestion example (local development):
 
@@ -65,27 +69,41 @@ Iterating over threads:
     for thread in reader.iter_threads("subject:Interview"):
         print(thread.normalized_subject, len(thread.messages))
 
-----------------------------------------------------------------------
+---
-Extensibility Model
+
-----------------------------------------------------------------------
+## Architecture
 
 Mail Intake is designed to be extensible via **public contracts** exposed
 through its modules:
 
-- Users MAY implement their own mail adapters by subclassing
+- Users MAY implement their own mail adapters by subclassing ``adapters.MailIntakeAdapter``
-  ``adapters.MailIntakeAdapter``
+- Users MAY implement their own authentication providers by subclassing ``auth.MailIntakeAuthProvider[T]``
-- Users MAY implement their own authentication providers by subclassing
+- Users MAY implement their own credential persistence layers by implementing ``credentials.CredentialStore[T]``
-  ``auth.MailIntakeAuthProvider[T]``
-- Users MAY implement their own credential persistence layers by
-  implementing ``credentials.CredentialStore[T]``
 
 Users SHOULD NOT subclass built-in adapter implementations. Built-in
 adapters (such as Gmail) are reference implementations and may change
 internally without notice.
 
-----------------------------------------------------------------------
+**Design Guarantees:**
-Public API Surface
+- Read-only access: no mutation of provider state
-----------------------------------------------------------------------
+- Provider-agnostic domain models
+- Explicit configuration and dependency injection
+- No implicit global state or environment reads
+- Deterministic, testable behavior
+- Distributed-safe authentication design
+
+Mail Intake favors correctness, clarity, and explicitness over convenience
+shortcuts.
+
+**Core Philosophy:**
+`Mail Intake` is built as a **contract-first ingestion pipeline**:
+1. **Layered Decoupling**: Adapters handle transport, Parsers handle format normalization, and Ingestion orchestrates.
+2. **Provider Agnosticism**: Domain models and core logic never depend on provider-specific (e.g., Gmail) API internals.
+3. **Stateless Workflows**: The library functions as a read-only pipe, ensuring side-effect-free ingestion.
+
+---
+
+## Public API
 
 The supported public API consists of the following top-level modules:
 
@@ -101,40 +119,7 @@ The supported public API consists of the following top-level modules:
 Classes and functions should be imported explicitly from these modules.
 No individual symbols are re-exported at the package root.
 
-----------------------------------------------------------------------
+---
-Design Guarantees
-----------------------------------------------------------------------
-
-- Read-only access: no mutation of provider state
-- Provider-agnostic domain models
-- Explicit configuration and dependency injection
-- No implicit global state or environment reads
-- Deterministic, testable behavior
-- Distributed-safe authentication design
-
-Mail Intake favors correctness, clarity, and explicitness over convenience
-shortcuts.
-
-## Core Philosophy
-
-`Mail Intake` is built as a **contract-first ingestion pipeline**:
-
-1. **Layered Decoupling**: Adapters handle transport, Parsers handle format normalization, and Ingestion orchestrates.
-2. **Provider Agnosticism**: Domain models and core logic never depend on provider-specific (e.g., Gmail) API internals.
-3. **Stateless Workflows**: The library functions as a read-only pipe, ensuring side-effect-free ingestion.
-
-## Documentation Design
-
-Follow these "AI-Native" docstring principles across the codebase:
-
-### For Humans
-- **Namespace Clarity**: Always specify which module a class or function belongs to.
-- **Contract Explanations**: Use the `adapters` and `auth` base classes to explain extension requirements.
-
-### For LLMs
-- **Dotted Paths**: Use full dotted paths in docstrings to help agents link concepts across modules.
-- **Typed Interfaces**: Provide `.pyi` stubs for every public module to ensure perfect context for AI coding tools.
-- **Canonical Exceptions**: Always use `: description` pairs in `Raises` blocks to enable structured error analysis.
 """
 
 

mail_intake/adapters/__init__.py

@@ -1,6 +1,10 @@
 """
 Mail provider adapter implementations for Mail Intake.
 
+---
+
+## Summary
+
 This package contains **adapter-layer implementations** responsible for
 interfacing with external mail providers and exposing a normalized,
 provider-agnostic contract to the rest of the system.
@@ -15,8 +19,14 @@ Provider-specific logic **must not leak** outside of adapter implementations.
 All parsings, normalizations, and transformations must be handled by downstream
 components.
 
-Public adapters exported from this package are considered the supported
+---
-integration surface for mail providers.
+
+## Public API
+
+    MailIntakeAdapter
+    MailIntakeGmailAdapter
+
+---
 """
 
 from .base import MailIntakeAdapter

mail_intake/adapters/base.py

@@ -1,6 +1,10 @@
 """
 Mail provider adapter contracts for Mail Intake.
 
+---
+
+## Summary
+
 This module defines the **provider-agnostic adapter interface** used for
 read-only mail ingestion.
 
@@ -17,12 +21,16 @@ class MailIntakeAdapter(ABC):
     """
     Base adapter interface for mail providers.
 
-    This interface defines the minimal contract required to:
+    Notes:
-    - Discover messages matching a query
+        **Guarantees:**
-    - Retrieve full message payloads
-    - Retrieve full thread payloads
 
-    Adapters are intentionally read-only and must not mutate provider state.
+            - discover messages matching a query
+            - retrieve full message payloads
+            - retrieve full thread payloads
+
+        **Lifecycle:**
+
+            - adapters are intentionally read-only and must not mutate provider state
     """
 
     @abstractmethod
@@ -30,17 +38,22 @@ class MailIntakeAdapter(ABC):
         """
         Iterate over lightweight message references matching a query.
 
-        Implementations must yield dictionaries containing at least:
-        - ``message_id``: Provider-specific message identifier
-        - ``thread_id``: Provider-specific thread identifier
-
         Args:
-            query: Provider-specific query string used to filter messages.
+            query (str):
+                Provider-specific query string used to filter messages.
 
         Yields:
+            Dict[str, str]:
                 Dictionaries containing message and thread identifiers.
 
-        Example yield:
+        Notes:
+            **Guarantees:**
+
+                - Implementations must yield dictionaries containing at least ``message_id`` and ``thread_id``
+
+        Example:
+            Typical yield:
+
                 {
                     "message_id": "...",
                     "thread_id": "..."
@@ -54,11 +67,12 @@ class MailIntakeAdapter(ABC):
         Fetch a full raw message by message identifier.
 
         Args:
-            message_id: Provider-specific message identifier.
+            message_id (str):
+                Provider-specific message identifier.
 
         Returns:
-            Provider-native message payload
+            Dict[str, Any]:
-            (e.g., Gmail message JSON structure).
+                Provider-native message payload (e.g., Gmail message JSON structure).
         """
         raise NotImplementedError
 
@@ -68,9 +82,11 @@ class MailIntakeAdapter(ABC):
         Fetch a full raw thread by thread identifier.
 
         Args:
-            thread_id: Provider-specific thread identifier.
+            thread_id (str):
+                Provider-specific thread identifier.
 
         Returns:
+            Dict[str, Any]:
                 Provider-native thread payload.
         """
         raise NotImplementedError

mail_intake/adapters/gmail.py

@@ -1,6 +1,10 @@
 """
 Gmail adapter implementation for Mail Intake.
 
+---
+
+## Summary
+
 This module provides a **Gmail-specific implementation** of the
 `MailIntakeAdapter` contract.
 
@@ -30,12 +34,15 @@ class MailIntakeGmailAdapter(MailIntakeAdapter):
     Gmail REST API. It translates the generic mail intake contract into
     Gmail-specific API calls.
 
-    This class is the ONLY place where:
+    Notes:
-    - googleapiclient is imported
+        **Responsibilities:**
+
+            - This class is the ONLY place where googleapiclient is imported
             - Gmail REST semantics are known
             - .execute() is called
 
-    Design constraints:
+        **Constraints:**
+        
             - Must remain thin and imperative
             - Must not perform parsing or interpretation
             - Must not expose Gmail-specific types beyond this class
@@ -50,9 +57,11 @@ class MailIntakeGmailAdapter(MailIntakeAdapter):
         Initialize the Gmail adapter.
 
         Args:
-            auth_provider: Authentication provider capable of supplying
+            auth_provider (MailIntakeAuthProvider):
-                valid Gmail API credentials.
+                Authentication provider capable of supplying valid Gmail API credentials.
-            user_id: Gmail user identifier. Defaults to `"me"`.
+
+            user_id (str):
+                Gmail user identifier. Defaults to `"me"`.
         """
         self._auth_provider = auth_provider
         self._user_id = user_id
@@ -64,10 +73,12 @@ class MailIntakeGmailAdapter(MailIntakeAdapter):
         Lazily initialize and return the Gmail API service client.
 
         Returns:
+            Any:
                 Initialized Gmail API service instance.
 
         Raises:
-            MailIntakeAdapterError: If the Gmail service cannot be initialized.
+            MailIntakeAdapterError:
+                If the Gmail service cannot be initialized.
         """
         if self._service is None:
             try:
@@ -84,15 +95,16 @@ class MailIntakeGmailAdapter(MailIntakeAdapter):
         Iterate over message references matching the query.
 
         Args:
-            query: Gmail search query string.
+            query (str):
+                Gmail search query string.
 
         Yields:
-            Dictionaries containing:
+            Dict[str, str]:
-            - ``message_id``: Gmail message ID
+                Dictionaries containing ``message_id`` and ``thread_id``.
-            - ``thread_id``: Gmail thread ID
 
         Raises:
-            MailIntakeAdapterError: If the Gmail API returns an error.
+            MailIntakeAdapterError:
+                If the Gmail API returns an error.
         """
         try:
             request = (
@@ -126,13 +138,16 @@ class MailIntakeGmailAdapter(MailIntakeAdapter):
         Fetch a full Gmail message by message ID.
 
         Args:
-            message_id: Gmail message identifier.
+            message_id (str):
+                Gmail message identifier.
 
         Returns:
+            Dict[str, Any]:
                 Provider-native Gmail message payload.
 
         Raises:
-            MailIntakeAdapterError: If the Gmail API returns an error.
+            MailIntakeAdapterError:
+                If the Gmail API returns an error.
         """
         try:
             return (
@@ -151,13 +166,16 @@ class MailIntakeGmailAdapter(MailIntakeAdapter):
         Fetch a full Gmail thread by thread ID.
 
         Args:
-            thread_id: Gmail thread identifier.
+            thread_id (str):
+                Gmail thread identifier.
 
         Returns:
+            Dict[str, Any]:
                 Provider-native Gmail thread payload.
 
         Raises:
-            MailIntakeAdapterError: If the Gmail API returns an error.
+            MailIntakeAdapterError:
+                If the Gmail API returns an error.
         """
         try:
             return (

mail_intake/auth/__init__.py

@@ -1,6 +1,10 @@
 """
 Authentication provider implementations for Mail Intake.
 
+---
+
+## Summary
+
 This package defines the **authentication layer** used by mail adapters
 to obtain provider-specific credentials.
 
@@ -15,6 +19,15 @@ Authentication providers:
 
 Consumers should depend on the abstract interface and use concrete
 implementations only where explicitly required.
+
+---
+
+## Public API
+
+    MailIntakeAuthProvider
+    MailIntakeGoogleAuth
+
+---
 """
 
 from .base import MailIntakeAuthProvider

mail_intake/auth/base.py

@@ -1,6 +1,10 @@
 """
 Authentication provider contracts for Mail Intake.
 
+---
+
+## Summary
+
 This module defines the **authentication abstraction layer** used by mail
 adapters to obtain provider-specific credentials.
 
@@ -23,15 +27,18 @@ class MailIntakeAuthProvider(ABC, Generic[T]):
     providers and mail adapters by requiring providers to explicitly
     declare the type of credentials they return.
 
-    Authentication providers encapsulate all logic required to:
+    Notes:
+        **Responsibilities:**
+
             - Acquire credentials from an external provider
             - Refresh or revalidate credentials as needed
             - Handle authentication-specific failure modes
             - Coordinate with credential persistence layers where applicable
 
-    Mail adapters must treat returned credentials as opaque and
+        **Constraints:**
-    provider-specific, relying only on the declared credential type
+        
-    expected by the adapter.
+            - Mail adapters must treat returned credentials as opaque and provider-specific
+            - Mail adapters rely only on the declared credential type expected by the adapter
     """
 
     @abstractmethod
@@ -39,15 +46,8 @@ class MailIntakeAuthProvider(ABC, Generic[T]):
         """
         Retrieve valid, provider-specific credentials.
 
-        This method is synchronous by design and represents the sole
-        entry point through which adapters obtain authentication
-        material.
-
-        Implementations must either return credentials of the declared
-        type ``T`` that are valid at the time of return or raise an
-        authentication-specific exception.
-
         Returns:
+            T:
                 Credentials of type ``T`` suitable for immediate use by the
                 corresponding mail adapter.
 
@@ -55,5 +55,12 @@ class MailIntakeAuthProvider(ABC, Generic[T]):
             Exception:
                 An authentication-specific exception indicating that
                 credentials could not be obtained or validated.
+
+        Notes:
+            **Guarantees:**
+
+                - This method is synchronous by design
+                - Represents the sole entry point through which adapters obtain authentication material
+                - Implementations must either return credentials of the declared type ``T`` that are valid at the time of return or raise an exception
         """
         raise NotImplementedError

mail_intake/auth/google.py

@@ -1,6 +1,10 @@
 """
 Google authentication provider implementation for Mail Intake.
 
+---
+
+## Summary
+
 This module provides a **Google OAuth–based authentication provider**
 used primarily for Gmail access.
 
@@ -33,13 +37,17 @@ class MailIntakeGoogleAuth(MailIntakeAuthProvider):
     This provider implements the `MailIntakeAuthProvider` interface using
     Google's OAuth 2.0 flow and credential management libraries.
 
-    Responsibilities:
+    Notes:
+        **Responsibilities:**
+
             - Load cached credentials from a credential store when available
             - Refresh expired credentials when possible
             - Initiate an interactive OAuth flow only when required
             - Persist refreshed or newly obtained credentials via the store
 
-    This class is synchronous by design and maintains a minimal internal state.
+        **Guarantees:**
+
+            - This class is synchronous by design and maintains a minimal internal state
     """
 
     def __init__(
@@ -52,15 +60,13 @@ class MailIntakeGoogleAuth(MailIntakeAuthProvider):
         Initialize the Google authentication provider.
 
         Args:
-            credentials_path:
+            credentials_path (str):
-                Path to the Google OAuth client secrets file used to
+                Path to the Google OAuth client secrets file used to initiate the OAuth 2.0 flow.
-                initiate the OAuth 2.0 flow.
 
-            store:
+            store (CredentialStore[Credentials]):
-                Credential store responsible for persisting and
+                Credential store responsible for persisting and retrieving Google OAuth credentials.
-                retrieving Google OAuth credentials.
 
-            scopes:
+            scopes (Sequence[str]):
                 OAuth scopes required for Gmail access.
         """
         self.credentials_path = credentials_path
@@ -71,19 +77,23 @@ class MailIntakeGoogleAuth(MailIntakeAuthProvider):
         """
         Retrieve valid Google OAuth credentials.
 
-        This method attempts to:
-        1. Load cached credentials from the configured credential store
-        2. Refresh expired credentials when possible
-        3. Perform an interactive OAuth login as a fallback
-        4. Persist valid credentials for future use
-
         Returns:
+            Credentials:
                 A ``google.oauth2.credentials.Credentials`` instance suitable
                 for use with Google API clients.
 
         Raises:
-            MailIntakeAuthError: If credentials cannot be loaded, refreshed,
+            MailIntakeAuthError:
+                If credentials cannot be loaded, refreshed,
                 or obtained via interactive authentication.
+
+        Notes:
+            **Lifecycle:**
+
+                - Load cached credentials from the configured credential store
+                - Refresh expired credentials when possible
+                - Perform an interactive OAuth login as a fallback
+                - Persist valid credentials for future use
         """
         creds = self.store.load()
 

mail_intake/config.py

@@ -1,6 +1,10 @@
 """
 Global configuration models for Mail Intake.
 
+---
+
+## Summary
+
 This module defines the **top-level configuration object** used to control
 mail ingestion behavior across adapters, authentication providers, and
 ingestion workflows.
@@ -18,28 +22,37 @@ class MailIntakeConfig:
     """
     Global configuration for mail-intake.
 
-    This configuration is intentionally explicit and immutable.
+    Notes:
-    No implicit environment reads or global state.
+        **Guarantees:**
 
-    Design principles:
+            - This configuration is intentionally explicit and immutable
-    - Immutable once constructed
+            - No implicit environment reads or global state
             - Explicit configuration over implicit defaults
             - No direct environment or filesystem access
-
+            - This model is safe to pass across layers and suitable for serialization
-    This model is safe to pass across layers and suitable for serialization.
     """
 
     provider: str = "gmail"
-    """Identifier of the mail provider to use (e.g., ``"gmail"``)."""
+    """
+    Identifier of the mail provider to use (e.g., ``"gmail"``).
+    """
 
     user_id: str = "me"
-    """Provider-specific user identifier. Defaults to the authenticated user."""
+    """
+    Provider-specific user identifier. Defaults to the authenticated user.
+    """
 
     readonly: bool = True
-    """Whether ingestion should operate in read-only mode."""
+    """
+    Whether ingestion should operate in read-only mode.
+    """
 
     credentials_path: Optional[str] = None
-    """Optional path to provider credentials configuration."""
+    """
+    Optional path to provider credentials configuration.
+    """
 
     token_path: Optional[str] = None
-    """Optional path to persisted authentication tokens."""
+    """
+    Optional path to persisted authentication tokens.
+    """

mail_intake/credentials/__init__.py

@@ -1,6 +1,10 @@
 """
 Credential persistence interfaces and implementations for Mail Intake.
 
+---
+
+## Summary
+
 This package defines the abstractions and concrete implementations used
 to persist authentication credentials across Mail Intake components.
 
@@ -16,6 +20,16 @@ The package provides:
 
 Credential lifecycle management, interpretation, and security policy
 decisions remain the responsibility of authentication providers.
+
+---
+
+## Public API
+
+    CredentialStore
+    PickleCredentialStore
+    RedisCredentialStore
+
+---
 """
 
 from mail_intake.credentials.store import CredentialStore

mail_intake/credentials/pickle.py

@@ -1,6 +1,10 @@
 """
 Local filesystem–based credential persistence for Mail Intake.
 
+---
+
+## Summary
+
 This module provides a file-backed implementation of the
 ``CredentialStore`` abstraction using Python's ``pickle`` module.
 
@@ -29,13 +33,16 @@ class PickleCredentialStore(CredentialStore[T]):
     filesystem. It is a simple implementation intended primarily for
     development, testing, and single-process execution contexts.
 
-    This implementation:
+    Notes:
+        **Guarantees:**
+
             - Stores credentials on the local filesystem
             - Uses pickle for serialization and deserialization
             - Does not provide encryption, locking, or concurrency guarantees
 
-    Credential lifecycle management, validation, and refresh logic are
+        **Constraints:**
-    explicitly out of scope for this class.
+        
+            - Credential lifecycle management, validation, and refresh logic are explicitly out of scope for this class
     """
 
     def __init__(self, path: str):
@@ -43,7 +50,7 @@ class PickleCredentialStore(CredentialStore[T]):
         Initialize a pickle-backed credential store.
 
         Args:
-            path:
+            path (str):
                 Filesystem path where credentials will be stored.
                 The file will be created or overwritten as needed.
         """
@@ -53,15 +60,16 @@ class PickleCredentialStore(CredentialStore[T]):
         """
         Load credentials from the local filesystem.
 
-        If the credential file does not exist or cannot be successfully
-        deserialized, this method returns ``None``.
-
-        The store does not attempt to validate or interpret the returned
-        credentials.
-
         Returns:
+            Optional[T]:
                 An instance of type ``T`` if credentials are present and
                 successfully deserialized; otherwise ``None``.
+
+        Notes:
+            **Guarantees:**
+
+                - If the credential file does not exist or cannot be successfully deserialized, this method returns ``None``
+                - The store does not attempt to validate or interpret the returned credentials
         """
         try:
             with open(self.path, "rb") as fh:
@@ -73,12 +81,14 @@ class PickleCredentialStore(CredentialStore[T]):
         """
         Persist credentials to the local filesystem.
 
-        Any previously stored credentials at the configured path are
-        overwritten.
-
         Args:
-            credentials:
+            credentials (T):
                 The credential object to persist.
+
+        Notes:
+            **Responsibilities:**
+
+                - Any previously stored credentials at the configured path are overwritten
         """
         with open(self.path, "wb") as fh:
             pickle.dump(credentials, fh)
@@ -87,8 +97,10 @@ class PickleCredentialStore(CredentialStore[T]):
         """
         Remove persisted credentials from the local filesystem.
 
-        This method deletes the credential file if it exists and should
+        Notes:
-        be treated as an idempotent operation.
+            **Lifecycle:**
+
+                - This method deletes the credential file if it exists and should be treated as an idempotent operation
         """
         import os
 

mail_intake/credentials/redis.py

@@ -1,6 +1,10 @@
 """
 Redis-backed credential persistence for Mail Intake.
 
+---
+
+## Summary
+
 This module provides a Redis-based implementation of the
 ``CredentialStore`` abstraction, enabling credential persistence
 across distributed and horizontally scaled deployments.
@@ -37,14 +41,16 @@ class RedisCredentialStore(CredentialStore[T]):
     distributed and horizontally scaled deployments where credentials
     must be shared across multiple processes or nodes.
 
-    The store is intentionally generic and delegates all serialization
+    Notes:
-    concerns to caller-provided functions. This avoids unsafe mechanisms
+        **Responsibilities:**
-    such as pickle and allows credential formats to be explicitly
-    controlled and audited.
 
-    This class is responsible only for persistence and retrieval.
+            - This class is responsible only for persistence and retrieval
-    It does not interpret, validate, refresh, or otherwise manage
+            - It does not interpret, validate, refresh, or otherwise manage the lifecycle of the credentials being stored
-    the lifecycle of the credentials being stored.
+
+        **Guarantees:**
+
+            - The store is intentionally generic and delegates all serialization concerns to caller-provided functions
+            - This avoids unsafe mechanisms such as pickle and allows credential formats to be explicitly controlled and audited
     """
 
     def __init__(
@@ -59,31 +65,20 @@ class RedisCredentialStore(CredentialStore[T]):
         Initialize a Redis-backed credential store.
 
         Args:
-            redis_client:
+            redis_client (Any):
-                An initialized Redis client instance (for example,
+                An initialized Redis client instance (for example, ``redis.Redis`` or a compatible interface) used to communicate with the Redis server.
-                ``redis.Redis`` or a compatible interface) used to
-                communicate with the Redis server.
 
-            key:
+            key (str):
-                The Redis key under which credentials are stored.
+                The Redis key under which credentials are stored. Callers are responsible for applying appropriate namespacing to avoid collisions.
-                Callers are responsible for applying appropriate
-                namespacing to avoid collisions.
 
-            serialize:
+            serialize (Callable[[T], bytes]):
-                A callable that converts a credential object of type
+                A callable that converts a credential object of type ``T`` into a ``bytes`` representation suitable for storage in Redis.
-                ``T`` into a ``bytes`` representation suitable for
-                storage in Redis.
 
-            deserialize:
+            deserialize (Callable[[bytes], T]):
-                A callable that converts a ``bytes`` payload retrieved
+                A callable that converts a ``bytes`` payload retrieved from Redis back into a credential object of type ``T``.
-                from Redis back into a credential object of type ``T``.
 
-            ttl_seconds:
+            ttl_seconds (Optional[int]):
-                Optional time-to-live (TTL) for the stored credentials,
+                Optional time-to-live (TTL) for the stored credentials, expressed in seconds. When provided, Redis will automatically expire the stored credentials after the specified duration. If ``None``, credentials are stored without an expiration.
-                expressed in seconds. When provided, Redis will
-                automatically expire the stored credentials after the
-                specified duration. If ``None``, credentials are stored
-                without an expiration.
         """
         self.redis = redis_client
         self.key = key
@@ -95,16 +90,16 @@ class RedisCredentialStore(CredentialStore[T]):
         """
         Load credentials from Redis.
 
-        If no value exists for the configured key, or if the stored
-        payload cannot be successfully deserialized, this method
-        returns ``None``.
-
-        The store does not attempt to validate the returned credentials
-        or determine whether they are expired or otherwise usable.
-
         Returns:
+            Optional[T]:
                 An instance of type ``T`` if credentials are present and
                 successfully deserialized; otherwise ``None``.
+
+        Notes:
+            **Guarantees:**
+
+                - If no value exists for the configured key, or if the stored payload cannot be successfully deserialized, this method returns ``None``
+                - The store does not attempt to validate the returned credentials or determine whether they are expired or otherwise usable
         """
         raw = self.redis.get(self.key)
         if not raw:
@@ -118,13 +113,15 @@ class RedisCredentialStore(CredentialStore[T]):
         """
         Persist credentials to Redis.
 
-        Any previously stored credentials under the same key are
-        overwritten. If a TTL is configured, the credentials will
-        expire automatically after the specified duration.
-
         Args:
-            credentials:
+            credentials (T):
                 The credential object to persist.
+
+        Notes:
+            **Responsibilities:**
+
+                - Any previously stored credentials under the same key are overwritten
+                - If a TTL is configured, the credentials will expire automatically after the specified duration
         """
         payload = self.serialize(credentials)
         if self.ttl_seconds:
@@ -136,7 +133,10 @@ class RedisCredentialStore(CredentialStore[T]):
         """
         Remove stored credentials from Redis.
 
-        This operation deletes the configured Redis key if it exists.
+        Notes:
-        Implementations should treat this method as idempotent.
+            **Lifecycle:**
+
+                - This operation deletes the configured Redis key if it exists
+                - Implementations should treat this method as idempotent
         """
         self.redis.delete(self.key)

mail_intake/credentials/store.py

@@ -1,6 +1,10 @@
 """
 Credential persistence abstractions for Mail Intake.
 
+---
+
+## Summary
+
 This module defines the generic persistence contract used to store and
 retrieve authentication credentials across Mail Intake components.
 
@@ -29,13 +33,15 @@ class CredentialStore(ABC, Generic[T]):
     Abstract base class defining a generic persistence interface for
     authentication credentials.
 
-    This interface separates *credential lifecycle management* from
+    Notes:
-    *credential storage mechanics*. Implementations are responsible
+        **Responsibilities:**
-    only for persistence concerns, while authentication providers
-    retain full control over credential creation, validation, refresh,
-    and revocation logic.
 
-    The store is intentionally agnostic to:
+            - Provide persistent storage separating life-cycle management from storage mechanics
+            - Keep implementation focused only on persistence
+            
+        **Constraints:**
+        
+            - The store is intentionally agnostic to:
                 - The concrete credential type being stored
                 - The serialization format used to persist credentials
                 - The underlying storage backend or durability guarantees
@@ -46,16 +52,16 @@ class CredentialStore(ABC, Generic[T]):
         """
         Load previously persisted credentials.
 
-        Implementations should return ``None`` when no credentials are
-        present or when stored credentials cannot be successfully
-        decoded or deserialized.
-
-        The store must not attempt to validate, refresh, or otherwise
-        interpret the returned credentials.
-
         Returns:
+            Optional[T]:
                 An instance of type ``T`` if credentials are available and
                 loadable; otherwise ``None``.
+
+        Notes:
+            **Guarantees:**
+
+                - Implementations should return ``None`` when no credentials are present or when stored credentials cannot be successfully decoded or deserialized
+                - The store must not attempt to validate, refresh, or otherwise interpret the returned credentials
         """
 
     @abstractmethod
@@ -63,18 +69,20 @@ class CredentialStore(ABC, Generic[T]):
         """
         Persist credentials to the underlying storage backend.
 
-        This method is invoked when credentials are newly obtained or
+        Args:
-        have been refreshed and are known to be valid at the time of
+            credentials (T):
-        persistence.
+                The credential object to persist.
+
+        Notes:
+            **Lifecycle:**
+
+                - This method is invoked when credentials are newly obtained or have been refreshed and are known to be valid at the time of persistence
+
+            **Responsibilities:**
 
-        Implementations are responsible for:
                 - Ensuring durability appropriate to the deployment context
                 - Applying encryption or access controls where required
                 - Overwriting any previously stored credentials
-
-        Args:
-            credentials:
-                The credential object to persist.
         """
 
     @abstractmethod
@@ -82,9 +90,13 @@ class CredentialStore(ABC, Generic[T]):
         """
         Remove any persisted credentials from the store.
 
-        This method is called when credentials are known to be invalid,
+        Notes:
-        revoked, corrupted, or otherwise unusable, and must ensure that
+            **Lifecycle:**
-        no stale authentication material remains accessible.
 
-        Implementations should treat this operation as idempotent.
+                - This method is called when credentials are known to be invalid, revoked, corrupted, or otherwise unusable
+                - Must ensure that no stale authentication material remains accessible
+
+            **Guarantees:**
+
+                - Implementations should treat this operation as idempotent
         """

mail_intake/exceptions.py

@@ -1,6 +1,10 @@
 """
 Exception hierarchy for Mail Intake.
 
+---
+
+## Summary
+
 This module defines the **canonical exception types** used throughout the
 Mail Intake library.
 
@@ -14,11 +18,12 @@ class MailIntakeError(Exception):
     """
     Base exception for all Mail Intake errors.
 
-    This is the root of the Mail Intake exception hierarchy.
+    Notes:
-    All errors raised by the library must derive from this class.
+        **Guarantees:**
 
-    Consumers should generally catch this type when handling
+            - This is the root of the Mail Intake exception hierarchy
-    library-level failures.
+            - All errors raised by the library must derive from this class
+            - Consumers should generally catch this type when handling library-level failures
     """
 
 
@@ -26,8 +31,10 @@ class MailIntakeAuthError(MailIntakeError):
     """
     Authentication and credential-related failures.
 
-    Raised when authentication providers are unable to acquire,
+    Notes:
-    refresh, or persist valid credentials.
+        **Lifecycle:**
+
+            - Raised when authentication providers are unable to acquire, refresh, or persist valid credentials
     """
 
 
@@ -35,8 +42,10 @@ class MailIntakeAdapterError(MailIntakeError):
     """
     Errors raised by mail provider adapters.
 
-    Raised when a provider adapter encounters API errors,
+    Notes:
-    transport failures, or invalid provider responses.
+        **Lifecycle:**
+
+            - Raised when a provider adapter encounters API errors, transport failures, or invalid provider responses
     """
 
 
@@ -44,6 +53,8 @@ class MailIntakeParsingError(MailIntakeError):
     """
     Errors encountered while parsing message content.
 
-    Raised when raw provider payloads cannot be interpreted
+    Notes:
-    or normalized into internal domain models.
+        **Lifecycle:**
+
+            - Raised when raw provider payloads cannot be interpreted or normalized into internal domain models
     """

mail_intake/ingestion/__init__.py

@@ -1,6 +1,10 @@
 """
 Mail ingestion orchestration for Mail Intake.
 
+---
+
+## Summary
+
 This package contains **high-level ingestion components** responsible for
 coordinating mail retrieval, parsing, normalization, and model construction.
 
@@ -15,6 +19,14 @@ Components in this package:
 
 Consumers are expected to construct a mail adapter and pass it to the
 ingestion layer to begin processing messages and threads.
+
+---
+
+## Public API
+
+    MailIntakeReader
+
+---
 """
 
 from .reader import MailIntakeReader

mail_intake/ingestion/reader.py

@@ -1,6 +1,10 @@
 """
 High-level mail ingestion orchestration for Mail Intake.
 
+---
+
+## Summary
+
 This module provides the primary, provider-agnostic entry point for
 reading and processing mail data.
 
@@ -29,19 +33,15 @@ class MailIntakeReader:
     """
     High-level read-only ingestion interface.
 
-    This class is the **primary entry point** for consumers of the Mail
+    Notes:
-    Intake library.
+        **Responsibilities:**
 
-    It orchestrates the full ingestion pipeline:
+            - This class is the primary entry point for consumers of the Mail Intake library
-    - Querying the adapter for message references
+            - It orchestrates the full ingestion pipeline: Querying the adapter for message references, fetching raw provider messages, parsing and normalizing message data, constructing domain models
-    - Fetching raw provider messages
-    - Parsing and normalizing message data
-    - Constructing domain models
 
-    This class is intentionally:
+        **Constraints:**
-    - Provider-agnostic
+        
-    - Stateless beyond iteration scope
+            - This class is intentionally: Provider-agnostic, stateless beyond iteration scope, read-only
-    - Read-only
     """
 
     def __init__(self, adapter: MailIntakeAdapter):
@@ -49,8 +49,8 @@ class MailIntakeReader:
         Initialize the mail reader.
 
         Args:
-            adapter: Mail adapter implementation used to retrieve raw
+            adapter (MailIntakeAdapter):
-                messages and threads from a mail provider.
+                Mail adapter implementation used to retrieve raw messages and threads from a mail provider.
         """
         self._adapter = adapter
 
@@ -59,13 +59,16 @@ class MailIntakeReader:
         Iterate over parsed messages matching a provider query.
 
         Args:
-            query: Provider-specific query string used to filter messages.
+            query (str):
+                Provider-specific query string used to filter messages.
 
         Yields:
+            MailIntakeMessage:
                 Fully parsed and normalized `MailIntakeMessage` instances.
 
         Raises:
-            MailIntakeParsingError: If a message cannot be parsed.
+            MailIntakeParsingError:
+                If a message cannot be parsed.
         """
         for ref in self._adapter.iter_message_refs(query):
             raw = self._adapter.fetch_message(ref["message_id"])
@@ -75,17 +78,22 @@ class MailIntakeReader:
         """
         Iterate over threads constructed from messages matching a query.
 
-        Messages are grouped by `thread_id` and yielded as complete thread
-        objects containing all associated messages.
-
         Args:
-            query: Provider-specific query string used to filter messages.
+            query (str):
+                Provider-specific query string used to filter messages.
 
-        Returns:
+        Yields:
+            MailIntakeThread:
                 An iterator of `MailIntakeThread` instances.
 
         Raises:
-            MailIntakeParsingError: If a message cannot be parsed.
+            MailIntakeParsingError:
+                If a message cannot be parsed.
+
+        Notes:
+            **Guarantees:**
+
+                - Messages are grouped by `thread_id` and yielded as complete thread objects containing all associated messages
         """
         threads: Dict[str, MailIntakeThread] = {}
 
@@ -110,14 +118,16 @@ class MailIntakeReader:
         Parse a raw provider message into a `MailIntakeMessage`.
 
         Args:
-            raw_message: Provider-native message payload.
+            raw_message (Dict[str, Any]):
+                Provider-native message payload.
 
         Returns:
+            MailIntakeMessage:
                 A fully populated `MailIntakeMessage` instance.
 
         Raises:
-            MailIntakeParsingError: If the message payload is missing required
+            MailIntakeParsingError:
-                fields or cannot be parsed.
+                If the message payload is missing required fields or cannot be parsed.
         """
         try:
             message_id = raw_message["id"]

mail_intake/models/__init__.py

@@ -1,6 +1,10 @@
 """
 Domain models for Mail Intake.
 
+---
+
+## Summary
+
 This package defines the **canonical, provider-agnostic data models**
 used throughout the Mail Intake ingestion pipeline.
 
@@ -11,6 +15,15 @@ Models in this package:
 - Serve as stable inputs for downstream processing and analysis
 
 These models form the core internal data contract of the library.
+
+---
+
+## Public API
+
+    MailIntakeMessage
+    MailIntakeThread
+
+---
 """
 
 from .message import MailIntakeMessage

mail_intake/models/message.py

@@ -1,6 +1,10 @@
 """
 Message domain models for Mail Intake.
 
+---
+
+## Summary
+
 This module defines the **canonical, provider-agnostic representation**
 of an individual email message as used internally by the Mail Intake
 ingestion pipeline.
@@ -19,37 +23,58 @@ class MailIntakeMessage:
     """
     Canonical internal representation of a single email message.
 
-    This model represents a fully parsed and normalized email message.
+    Notes:
-    It is intentionally provider-agnostic and suitable for persistence,
+        **Guarantees:**
-    indexing, and downstream processing.
 
-    No provider-specific identifiers, payloads, or API semantics
+            - This model represents a fully parsed and normalized email message
-    should appear in this model.
+            - It is intentionally provider-agnostic and suitable for persistence, indexing, and downstream processing
+
+        **Constraints:**
+        
+            - No provider-specific identifiers, payloads, or API semantics should appear in this model
     """
 
     message_id: str
-    """Provider-specific message identifier."""
+    """
+    Provider-specific message identifier.
+    """
 
     thread_id: str
-    """Provider-specific thread identifier to which this message belongs."""
+    """
+    Provider-specific thread identifier to which this message belongs.
+    """
 
     timestamp: datetime
-    """Message timestamp as a timezone-naive UTC datetime."""
+    """
+    Message timestamp as a timezone-naive UTC datetime.
+    """
 
     from_email: str
-    """Sender email address."""
+    """
+    Sender email address.
+    """
 
     from_name: Optional[str]
-    """Optional human-readable sender name."""
+    """
+    Optional human-readable sender name.
+    """
 
     subject: str
-    """Raw subject line of the message."""
+    """
+    Raw subject line of the message.
+    """
 
     body_text: str
-    """Extracted plain-text body content of the message."""
+    """
+    Extracted plain-text body content of the message.
+    """
 
     snippet: str
-    """Short provider-supplied preview snippet of the message."""
+    """
+    Short provider-supplied preview snippet of the message.
+    """
 
     raw_headers: Dict[str, str]
-    """Normalized mapping of message headers (header name → value)."""
+    """
+    Normalized mapping of message headers (header name → value).
+    """

mail_intake/models/thread.py

@@ -1,6 +1,10 @@
 """
 Thread domain models for Mail Intake.
 
+---
+
+## Summary
+
 This module defines the **canonical, provider-agnostic representation**
 of an email thread as used internally by the Mail Intake ingestion pipeline.
 
@@ -20,40 +24,53 @@ class MailIntakeThread:
     """
     Canonical internal representation of an email thread.
 
-    A thread groups multiple related messages under a single subject
+    Notes:
-    and participant set. It is designed to support reasoning over
+        **Guarantees:**
-    conversational context such as job applications, interviews,
-    follow-ups, and ongoing discussions.
 
-    This model is provider-agnostic and safe to persist.
+            - A thread groups multiple related messages under a single subject and participant set
+            - It is designed to support reasoning over conversational context such as job applications, interviews, follow-ups, and ongoing discussions
+            - This model is provider-agnostic and safe to persist
     """
 
     thread_id: str
-    """Provider-specific thread identifier."""
+    """
+    Provider-specific thread identifier.
+    """
 
     normalized_subject: str
-    """Normalized subject line used to group related messages."""
+    """
+    Normalized subject line used to group related messages.
+    """
 
     participants: Set[str] = field(default_factory=set)
-    """Set of unique participant email addresses observed in the thread."""
+    """
+    Set of unique participant email addresses observed in the thread.
+    """
 
     messages: List[MailIntakeMessage] = field(default_factory=list)
-    """Ordered list of messages belonging to this thread."""
+    """
+    Ordered list of messages belonging to this thread.
+    """
 
     last_activity_at: datetime | None = None
-    """Timestamp of the most recent message in the thread."""
+    """
+    Timestamp of the most recent message in the thread.
+    """
 
     def add_message(self, message: MailIntakeMessage) -> None:
         """
         Add a message to the thread and update derived fields.
 
-        This method:
+        Args:
+            message (MailIntakeMessage):
+                Parsed mail message to add to the thread.
+
+        Notes:
+            **Responsibilities:**
+
                 - Appends the message to the thread
                 - Tracks unique participants
                 - Updates the last activity timestamp
-
-        Args:
-            message: Parsed mail message to add to the thread.
         """
         self.messages.append(message)
 

mail_intake/parsers/__init__.py

@@ -1,6 +1,10 @@
 """
 Message parsing utilities for Mail Intake.
 
+---
+
+## Summary
+
 This package contains **provider-aware but adapter-agnostic parsing helpers**
 used to extract and normalize structured information from raw mail payloads.
 
@@ -16,6 +20,17 @@ This package does not:
 
 Parsing functions are designed to be composable and are orchestrated by the
 ingestion layer.
+
+---
+
+## Public API
+
+    extract_body
+    parse_headers
+    extract_sender
+    normalize_subject
+
+---
 """
 
 from .body import extract_body

mail_intake/parsers/headers.py

@@ -1,6 +1,10 @@
 """
 Message header parsing utilities for Mail Intake.
 
+---
+
+## Summary
+
 This module provides helper functions for normalizing and extracting
 useful information from provider-native message headers.
 
@@ -15,18 +19,23 @@ def parse_headers(raw_headers: List[Dict[str, str]]) -> Dict[str, str]:
     """
     Convert a list of Gmail-style headers into a normalized dict.
 
-    Provider payloads (such as Gmail) typically represent headers as a list
-    of name/value mappings. This function normalizes them into a
-    case-insensitive dictionary keyed by lowercase header names.
-
     Args:
-        raw_headers: List of header dictionaries, each containing
+        raw_headers (List[Dict[str, str]]):
-            ``name`` and ``value`` keys.
+            List of header dictionaries, each containing ``name`` and ``value`` keys.
 
     Returns:
+        Dict[str, str]:
             Dictionary mapping lowercase header names to stripped values.
 
+    Notes:
+        **Guarantees:**
+
+            - Provider payloads (such as Gmail) typically represent headers as a list of name/value mappings
+            - This function normalizes them into a case-insensitive dictionary keyed by lowercase header names
+
     Example:
+        Typical usage:
+        
             Input:
                 [
                     {"name": "From", "value": "John Doe <john@example.com>"},
@@ -57,22 +66,24 @@ def extract_sender(headers: Dict[str, str]) -> Tuple[str, Optional[str]]:
     """
     Extract sender email and optional display name from headers.
 
-    This function parses the ``From`` header and attempts to extract:
-    - Sender email address
-    - Optional human-readable display name
-
     Args:
-        headers: Normalized header dictionary as returned by
+        headers (Dict[str, str]):
-            :func:`parse_headers`.
+            Normalized header dictionary as returned by :func:`parse_headers`.
 
     Returns:
-        A tuple ``(email, name)`` where:
+        Tuple[str, Optional[str]]:
-        - ``email`` is the sender email address
+            A tuple ``(email, name)`` where ``email`` is the sender email address and ``name`` is the display name, or ``None`` if unavailable.
-        - ``name`` is the display name, or ``None`` if unavailable
 
-    Examples:
+    Notes:
-        ``"John Doe <john@example.com>"`` → ``("john@example.com", "John Doe")``
+        **Responsibilities:**
-        ``"john@example.com"`` → ``("john@example.com", None)``
+
+            - This function parses the ``From`` header and attempts to extract sender email address and optional human-readable display name
+
+    Example:
+        Typical values:
+
+            ``"John Doe <john@example.com>"`` -> ``("john@example.com", "John Doe")``
+            ``"john@example.com"`` -> ``("john@example.com", None)``
     """
     from_header = headers.get("from")
     if not from_header:

mail_intake/parsers/subject.py

@@ -1,6 +1,10 @@
 """
 Subject line normalization utilities for Mail Intake.
 
+---
+
+## Summary
+
 This module provides helper functions for normalizing email subject lines
 to enable reliable thread-level comparison and grouping.
 
@@ -12,27 +16,34 @@ import re
 
 
 _PREFIX_RE = re.compile(r"^(re|fw|fwd)\s*:\s*", re.IGNORECASE)
-"""Regular expression matching common reply/forward subject prefixes."""
+"""
+Regular expression matching common reply/forward subject prefixes.
+"""
 
 
 def normalize_subject(subject: str) -> str:
     """
     Normalize an email subject for thread-level comparison.
 
-    Operations:
+    Args:
+        subject (str):
+            Raw subject line from a message header.
+
+    Returns:
+        str:
+            Normalized subject string suitable for thread grouping.
+
+    Notes:
+        **Responsibilities:**
+
             - Strips common prefixes such as ``Re:``, ``Fwd:``, and ``FW:``
             - Repeats prefix stripping to handle stacked prefixes
             - Collapses excessive whitespace
             - Preserves original casing (no lowercasing)
 
-    This function is intentionally conservative and avoids aggressive
+        **Guarantees:**
-    transformations that could alter the semantic meaning of the subject.
 
-    Args:
+            - This function is intentionally conservative and avoids aggressive transformations that could alter the semantic meaning of the subject
-        subject: Raw subject line from a message header.
-
-    Returns:
-        Normalized subject string suitable for thread grouping.
     """
     if not subject:
         return ""