Composio · Gmail

Toolkit slug: gmail. Read the [[composio]] hub first for the call model (agent-swarm x composio …, user_id, connected accounts, the 4302 gotcha). Tool arguments go inside the request body; user_id defaults to "me" (the authorized account) — you usually don't need to set it.

# Direct execute (reliable path — pin the ACTIVE ca_… from the hub Recipe B)
agent-swarm x composio POST /tools/execute/<SLUG> \
  --body '{"user_id":"<connected-account-email>","connected_account_id":"<active-connected-account-id>","arguments":{ … }}'

Follow the hub's Resolve the user and connected account procedure, then select the resolved user's gmail account whose status is ACTIVE.

Headline tools

Slug	What	Key args
`GMAIL_FETCH_EMAILS`	List/search emails	`query`, `max_results` (def 1 — set it!), `include_payload` (def true), `verbose` (def true), `ids_only`, `label_ids`, `page_token`
`GMAIL_FETCH_MESSAGE_BY_MESSAGE_ID`	Full single message	`message_id`, `include_payload`
`GMAIL_FETCH_MESSAGE_BY_THREAD_ID`	All messages in a thread	`thread_id`
`GMAIL_LIST_THREADS`	List threads	`query`, `max_results`, `page_token`
`GMAIL_SEND_EMAIL`	Send	`recipient_email`, `subject`, `body`, `is_html` (def false), `cc`, `bcc`, `extra_recipients`, `attachment`
`GMAIL_REPLY_TO_THREAD`	Reply in-thread	`thread_id`, `message_body`, `recipient_email`
`GMAIL_CREATE_EMAIL_DRAFT` / `GMAIL_SEND_DRAFT`	Draft then send	`body`, `subject`, `recipient_email` / `draft_id`
`GMAIL_GET_PROFILE`	Whose mailbox is this?	—
`GMAIL_LIST_LABELS` / `GMAIL_CREATE_LABEL` / `GMAIL_ADD_LABEL_TO_EMAIL`	Labels	`message_id`, `label_ids` (use LIST_LABELS for custom IDs)
`GMAIL_GET_CONTACTS` / `GMAIL_SEARCH_PEOPLE`	Contacts	`query`
`GMAIL_GET_ATTACHMENT`	Download attachment	`message_id`, `attachment_id`

Full set: 63 tools — list with agent-swarm x composio GET "/tools?toolkit_slug=gmail&limit=100" | jq -r '.items[]|"\(.slug)\t\(.name)"'. Avoid the ones marked Deprecated (GMAIL_LIST_MESSAGES, GMAIL_REMOVE_LABEL).

Read recipe (metadata-first)

agent-swarm x composio POST /tools/execute/GMAIL_FETCH_EMAILS \
  --body '{"connected_account_id":"ca_…","arguments":{"max_results":5,"include_payload":false,"verbose":false}}'

Always set max_results — the default is 1.
Use Gmail query syntax: "is:unread", "from:foo@bar.com newer_than:7d", "subject:invoice has:attachment".
Keep include_payload:false + verbose:false unless the user needs full bodies (token-heavy). Use ids_only:true for the cheapest listing.

Send recipe

agent-swarm x composio POST /tools/execute/GMAIL_SEND_EMAIL \
  --body '{"connected_account_id":"ca_…","arguments":{
    "recipient_email":"someone@example.com",
    "subject":"Hello",
    "body":"<p>Hi there</p>",
    "is_html":true,
    "cc":["cc@example.com"]
  }}'

Set is_html:true when body contains HTML, otherwise it sends as literal text.
recipient_email is the primary; add more via extra_recipients / cc / bcc.
Sending is a write action — only do it when the task explicitly asks.

Reply in a thread

agent-swarm x composio POST /tools/execute/GMAIL_REPLY_TO_THREAD \
  --body '{"connected_account_id":"ca_…","arguments":{
    "thread_id":"<thread_id>","recipient_email":"someone@example.com","message_body":"thanks!"
  }}'

Gotchas

Default max_results is 1 — forgetting it makes "list my emails" return a single message.
Bodies/attachments are token-heavy and may contain secrets — default to metadata; the secret-scrubber doesn't run on Composio tool output.
If you get ToolRouterV2_NoActiveConnection, switch to direct execute with the pinned connected_account_id (hub Gotchas).