outlook-bridge
outlook-bridge
Servidor MCP para que Claude busque y lea correos en Outlook clásico (Windows,
vía COM) — list_folders, search_mail, read_mail, get_thread,
read_attachment. Consulta el diseño completo en
docs/superpowers/specs/2026-08-24-outlook-bridge-design.md
y el plan de implementación en
docs/superpowers/plans/2026-08-24-outlook-bridge-a.md.
Solo lectura — no hay herramientas de escritura
Este servidor no tiene send_mail, delete_mail, move_mail,
mark_as_read, ni ninguna herramienta que modifique, elimine o envíe correos. No hay ningún método
en Win32MailStore que llame a .Send(), .Save(), .Delete(), .Move(),
.MarkAsRead(), ni que asigne valores a una propiedad de Outlook. Única
excepción: read_attachment escribe el archivo adjunto en una carpeta temporal que el propio servidor
crea (tempfile.TemporaryDirectory) para extraer el texto, y luego elimina esa carpeta inmediatamente
después — SaveAsFile es una API de lectura, no modifica nada en Outlook.
Related MCP server: outlook-mcp
Ejecución en Linux (máquina de desarrollo) — FakeMailStore
No se necesita Outlook ni Windows. FakeMailStore carga un fixture YAML
(~50 correos sintéticos: varias carpetas, varios stores, hilos de conversación, archivos adjuntos
de todo tipo, correos en vietnamita, correos con cuerpo largo, correos vacíos, elementos que no son correos) e
implementa la misma interfaz MailStore que implementa Win32MailStore.
python -m venv .venv
.venv/bin/pip install -e ".[dev]"
# Chạy server với store giả (không cần Outlook)
OUTLOOK_BRIDGE_FAKE=1 OUTLOOK_BRIDGE_FIXTURE=tests/fixtures/mailbox.yaml \
.venv/bin/python server.pyEjecutar los tests
Linux (la mayor parte de la lógica — Python puro + FakeMailStore):
.venv/bin/pytestWindows (el conjunto de tests de contrato que se usa de forma COMPARTIDA para ambos stores — esta es la única
forma de demostrar que Win32MailStore realmente coincide en comportamiento con FakeMailStore,
no solo que "funciona"):
set OUTLOOK_BRIDGE_CONTRACT_WIN32=1
.venv\Scripts\pytest tests/contract -vAlgunos casos de este conjunto se omiten (SKIP) de forma intencionada en un buzón real (datos que solo existen
en el fixture de FakeMailStore) — consulta la sección "Tests SKIP intencionados" en
docs/WINDOWS-RUNBOOK.md antes de considerar un SKIP como señal de un problema.
Consulta docs/INSTALL-windows.md para instalar y registrar
el servidor MCP en Windows, y
docs/WINDOWS-RUNBOOK.md para la secuencia de pasos a seguir
cuando te sientes por primera vez ante una máquina Windows real.
Diagnóstico del entorno — doctor.py
python doctor.py # trên Linux: báo "không phải Windows", degrade an toàn
python doctor.py --verbose # trên Windows: thêm chi tiết root.Name, cây folder, giá trị rawResultado | Significado | Acción |
| La vía COM funciona | Listo para registrar el servidor MCP |
| Esta arquitectura no se puede usar en esa máquina | Detente — no hay plan de contingencia (riesgo R2 abajo) |
| Sigue siendo utilizable, pero la búsqueda por contenido del cuerpo hará fallback a un recorrido secuencial (más lento, con advertencia en los resultados) | Úsalo con normalidad |
Dos riesgos que nadie ha resuelto todavía (spec §13)
R2 — New Outlook irá reemplazando gradualmente a Outlook clásico, y COM desaparecerá con él.
Microsoft está forzando la migración de los usuarios a New Outlook, que no registra un
servidor COM (doctor.py informa com_ok: False cuando esto ocurre). Esto es algo
con fecha de caducidad, no un error que se pueda parchear. La única vía de salida cuando
ocurra es reescribir Win32MailStore sobre la Microsoft Graph API — la arquitectura
del proyecto (todo el detalle de COM reside únicamente en dos archivos, win32_store.py
y doctor.py) limita el daño a reescribir exactamente esos dos archivos, no
todo el sistema.
R3 — El contenido de los correos internos de la empresa pasa por la API de Anthropic. COM se ejecuta completamente en local (nada sale de la máquina para leer correos), pero para que Claude responda basándose en el contenido de los correos, ese contenido debe enviarse a la API. Esta es la contrapartida inherente de usar un asistente de IA para leer correos — ningún servidor puede resolverlo por ti.
Única medida de control: folder_allowlist en config.toml.
Configúralo como una lista de carpetas específicas (con calificación de store, por ejemplo
"Mailbox - Nguyen Van A/Inbox") para limitar el alcance de los correos que este servidor puede
ver — los correos fuera de la allowlist no se pueden leer con ninguna herramienta, por ninguna
vía de llamada (búsqueda, lectura por id, lectura de hilo, descarga de archivos adjuntos), incluso si
un hilo de conversación cruza el límite de la allowlist.
La coincidencia es EXACTA, no por prefijo. Permitir "Inbox" NO incluye
"Inbox/Bao cao" — cada carpeta que se quiera permitir debe estar listada por separado.
Esta es una decisión de diseño intencionada, no una limitación: una allowlist
por prefijo puede permitir fácilmente, sin querer, una subcarpeta sensible en la que la persona que configura
no había pensado. Si no se configura folder_allowlist (por defecto, lista
vacía), se pueden leer todas las carpetas del buzón — configúrala antes de apuntar
este servidor a un buzón corporativo real. Consulta el paso 2 de docs/WINDOWS-RUNBOOK.md
para saber cómo obtener los nombres de carpeta con calificación de store desde list_folders.
Si necesitas restringir aún más: reduce folder_allowlist a unas pocas carpetas específicas,
o — si aún no es suficiente — considera devolver solo metadatos + snippet en lugar del
contenido completo del correo (actualmente no hay ninguna herramienta que haga esto; haría falta una herramienta nueva).
Available Tools
5 toolsget_threadA
Lấy toàn bộ mail trong cùng luồng hội thoại, sắp từ cũ tới mới.
| Name | Required | Description | Default |
|---|---|---|---|
| limit | No | ||
| mail_id | Yes |
Output Schema
| Name | Required | Description |
|---|---|---|
| result | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the behavioral burden. It usefully discloses the sorting order (old to new) and the scope ('all emails in the thread'). However, it does not explain how the 'limit' parameter interacts with 'toàn bộ' (all), nor does it mention pagination, auth, or response shape.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single focused sentence with no filler. It front-loads the primary action and scope, and the sorting detail adds useful information without bloating the text.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
This is a relatively simple two-parameter tool with an output schema, so the description does not need to detail return values. Still, the meaning of 'limit', the potential conflict with 'all', and the absence of any usage boundaries leave a few gaps that an agent would have to infer.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 0%, so the description needs to clarify parameters, but it never mentions mail_id or limit. The phrase 'same conversation thread' indirectly implies the role of mail_id, but no direct mapping or additional meaning is provided for either parameter.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states a specific verb ('get') and a well-defined resource ('all emails in the same conversation thread'), and clarifies the ordering (old to new). This distinguishes it from siblings like read_mail, which targets a single message, and search_mail, which searches across mail.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description implies the use case: you call this when you need the full thread associated with a mail, rather than one individual message. However, it does not explicitly name alternatives or say when not to use it, so the guidance remains implicit rather than prescriptive.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
list_foldersA
Liệt kê cây folder của Outlook kèm số item và số mail chưa đọc.
| Name | Required | Description | Default |
|---|---|---|---|
No parameters | |||
Output Schema
| Name | Required | Description |
|---|---|---|
| result | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the behavioral disclosure burden. It does disclose meaningful return context by saying the folder tree includes item counts and unread mail counts. It does not explicitly state read-only behavior or access prerequisites, but for a parameterless list operation this is a moderate rather than severe gap.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single, tight sentence with the action and resource up front, followed by the two useful counts. There is no filler or repetition of the tool name.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a parameterless listing tool with an output schema, the description covers the essential behavior: it returns the Outlook folder tree with item and unread counts. It is slightly incomplete in not stating the scope of the tree (e.g., all folders vs. accessible folders) or any access caveats, but the output schema likely fills in return details.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The input schema has zero parameters, so the baseline is 4. There are no parameter semantics to explain, and the description appropriately focuses on what the tool returns rather than input details.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description names a specific verb and resource: listing the Outlook folder tree, and additionally specifies the included data (item count and unread mail count). This clearly separates it from siblings like read_mail, search_mail, get_thread, and read_attachment, which all operate on individual messages rather than the folder hierarchy.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description implies use when an agent needs an overview of Outlook folders and their counts, and the sibling tools are clearly message-oriented, so the intended context is reasonably inferable. However, it does not explicitly state when to use this tool versus alternatives or provide any exclusions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
read_attachmentA
Trích text từ một tệp đính kèm. ref là tên tệp hoặc chỉ số từ read_mail.
Hỗ trợ txt/csv/md/json/xml/pdf/xlsx/docx.
| Name | Required | Description | Default |
|---|---|---|---|
| ref | Yes | ||
| mail_id | Yes | ||
| max_chars | No |
Output Schema
| Name | Required | Description |
|---|---|---|
| result | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the behavioral burden. It states that the tool extracts text and supports specific formats, which is useful. However, it does not mention truncation via max_chars or behavior for unsupported attachment types, leaving some important behavioral gaps.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is concise and front-loaded with the core action, followed by ref semantics and supported formats. Every sentence adds useful information with no redundancy.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
This is a simple tool with an output schema, and the description covers the core purpose, ref semantics, and supported formats. It is adequate, but missing clarification about mail_id provenance and max_chars behavior leaves room for agent misinterpretation.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 0%, so the description must compensate. It usefully explains `ref` as a filename or index from read_mail. However, `mail_id` and `max_chars` are not described at all; their meanings are only inferable from the parameter names and default value.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description uses a specific verb and resource: 'Trích text từ một tệp đính kèm' (extract text from an attachment). This clearly differentiates it from sibling tools like read_mail, get_thread, list_folders, and search_mail, none of which target attachments.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description gives clear workflow context by stating that `ref` is a filename or index from read_mail, which tells the agent how the tool relates to a sibling. It does not explicitly list when not to use it, but the attachment-specific purpose makes the appropriate use case clear.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
read_mailA
Đọc nội dung đầy đủ của 1-10 mail theo handle từ search_mail. Liệt kê tên tệp đính kèm nhưng KHÔNG đọc nội dung tệp — dùng read_attachment cho việc đó.
| Name | Required | Description | Default |
|---|---|---|---|
| ids | Yes | ||
| max_body_chars | No |
Output Schema
| Name | Required | Description |
|---|---|---|
| result | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral disclosure burden. It transparently states the operation, the 1-10 email limit, and the boundary that attachment filenames are listed but file contents are not read. However, it omits the effect of max_body_chars on body truncation, which is relevant given the claim of reading 'full' content.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two short sentences, front-loaded with the core purpose, followed by a critical negative behavior and the correct alternative. Every sentence earns its place and there is no fluff.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
The tool has an output schema, so return values need not be described. The description covers the operation, input source, count limit, and attachment-handling boundary. The main gap is the undocumented behavior of max_body_chars, but the overall context is sufficient for safe invocation in most cases.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 0%, so the description must compensate. It usefully clarifies that ids are handles from search_mail and that 1-10 emails are supported, but it says nothing about max_body_chars, its default, or its truncation behavior. The description partially compensates for the missing schema descriptions but not fully.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description names a specific verb ('Đọc nội dung đầy đủ'), a precise resource (1-10 emails), and a clear source for those emails ('theo handle từ search_mail'). It also distinguishes itself from read_attachment by stating that it only lists attachment names and does not read file contents.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description clearly states when to use the tool — after search_mail, to read full email content — and explicitly directs the agent to read_attachment for attachment contents. It does not contrast against get_thread or list_folders, so the guidance is strong but not exhaustive across all siblings.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
search_mailA
Tìm mail. Trả danh sách gọn kèm handle (h1, h2...) để dùng cho read_mail.
query tìm trong nội dung mail; folder="*" tìm mọi folder.
Ngày theo định dạng YYYY-MM-DD.
| Name | Required | Description | Default |
|---|---|---|---|
| limit | No | ||
| query | No | ||
| since | No | ||
| until | No | ||
| folder | No | ||
| offset | No | ||
| sender | No | ||
| subject | No | ||
| unread_only | No | ||
| flagged_only | No | ||
| has_attachments | No |
Output Schema
| Name | Required | Description |
|---|---|---|
| result | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the disclosure burden. It reveals the compact list output, handle semantics, query scope, folder wildcard, and date format. However, it does not mention matching behavior, sorting, pagination semantics, or side-effect/safety profile; the disclosure is useful but partial.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Three short, purposeful sentences. The main purpose is front-loaded, the output/handle chain is stated next, and the parameter/date notes are dense but non-redundant.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
The description gives enough to start using the tool: output shape, handle purpose, folder wildcard, and date format. But with 11 parameters and no annotations, important semantics (limit/offset, sender/subject matching, boolean filters) are left to inference; the tool is functional but not fully specified.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 0% across 11 parameters, so the description must compensate. It adds meaning for query, folder (including '*' wildcard), and since/until date format, but leaves sender, subject, unread_only, flagged_only, has_attachments, limit, and offset without behavioral clarification beyond their names.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description starts with 'Tìm mail' (search mail), then states the output ('danh sách gọn kèm handle') and the downstream use (read_mail). This is a specific verb-plus-resource statement that clearly separates search_mail from siblings like read_mail, get_thread, and list_folders.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
It gives concrete usage cues: query searches mail content, folder='*' searches all folders, dates use YYYY-MM-DD, and returned handles feed read_mail. It stops short of naming when not to use search_mail or explicitly comparing alternatives, so it is not a full 5.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Tool Schema Changelog
Recent tool additions, removals, and schema changes observed during successful MCP inspections.
5 tool updates
v0.1.0- First observed
get_thread - First observed
list_folders - First observed
read_attachment - First observed
read_mail - First observed
search_mail
TDQS
Scored across 5 tools
Each tool targets a distinct aspect: thread retrieval, attachment extraction, individual mail reading, folder listing, and search. No two tools overlap in purpose, and the descriptions clarify the boundaries (e.g., read_mail vs get_thread).
All tool names follow a consistent verb_noun pattern in snake_case: get_thread, read_attachment, read_mail, list_folders, search_mail. The verbs are specific and predictable.
Five tools is well-scoped for an email read/search bridge. Each tool serves a clear, non-redundant function in the core workflow of finding and reading emails with attachments.
The tool surface covers the full read/search lifecycle: search returns handles, read_mail consumes them, get_thread expands conversations, list_folders scopes searches, and read_attachment handles file content. No obvious missing operations for the apparent read-only purpose.
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