MCP tool reference

The catalog below is built from the same definitions returned to MCP clients during tool discovery. Each reference page adds human requirements, prompts, examples, response expectations, and recovery guidance.

Native message attachments

linkedin_message accepts optional attachments. linkedin_invite_then_message accepts follow_up_attachments for the message sent after acceptance. Text stays required. Up to 5 files and 20,000,000 bytes combined per message, with 200 MB of private storage per workspace. PDF, MP4/MOV, PNG/JPG/GIF/BMP, Office documents and TXT/CSV/RTF are validated by extension, MIME type and content. HTML and executable files are unsupported. The provider can reject files that its selected inbox does not support.

For a local file, select it with the paperclip in the SalesTouch inbox. The application uploads chunks of at most 2 MB through the authenticated /api/linkedin/attachments flow, then finalizes the file. Use its attachment_id in an agent message. Clients can start an upload with POST /api/linkedin/attachments and account_id, filename, content_type, size_bytes; send raw chunks with POST /api/linkedin/attachments/{id}, Content-Type: application/octet-stream and Upload-Offset; finalize with PUT on that URL. GET returns status and the received byte offset, and DELETE removes an unused upload. The server never opens a caller-supplied local path.

An agent can alternatively provide content_base64 (canonical base64 without a data URL prefix) or a public HTTPS url, with filename and content_type. URLs use port 443; private and reserved networks, unsafe redirects and downloads exceeding 15 seconds are rejected. All modes persist private file bytes before queueing. Native media previews are the default; send_mode: "file" requests a downloadable file where supported.

queue and scheduled_for retain attachment references with the action. Acceptance follow-ups retain files for up to 90 days after the scheduled invitation; unfinished uploads expire after 24 hours and delivered files after 7 days. Pending queued sends retain their files until delivery. Unknown outcomes retain their diagnostic metadata and block automatic resend.

Reuse idempotency_key when retrying an attachment message. Without a key, identical recipient, text and files are deduplicated. Use a new key only for an intentional new message. Responses include attachment_delivery_id, status and attachment IDs; follow-up responses expose these under follow_up. Inspect delivery status with the authenticated GET /api/linkedin/attachment-deliveries/{id} endpoint. ATTACHMENT_SEND_UNCERTAIN requires checking the conversation before another send. Upload, ownership, content, size and URL errors use explicit attachment error codes.

{
  "identifier": "https://www.linkedin.com/in/example",
  "text": "Here is the brochure we discussed.",
  "attachments": [{"filename": "brochure.pdf", "content_type": "application/pdf", "url": "https://example.com/brochure.pdf"}],
  "idempotency_key": "brochure-prospect-2026-10",
  "queue": true
}