Documentation

Quickstart

One REST API - and MCP server - for sending, inboxes and forwarding. Create an inbox, send an email and verify a domain in about a minute.

API reference MCP server OpenAPI llms.txt

Authentication

Every request to /v1 is authenticated with a bearer key in the Authorization header. Live keys start with sk_live_; test-mode keys start with sk_test_. The base URL is https://threadcamp.vercel.app/v1.

To try the API with no signup, use the public sandbox key sk_test_sandbox_threadcamp_public_demo. Every response carries an x-request-id header for support.

Authorization: Bearer sk_live_...
# base URL
https://threadcamp.vercel.app/v1

60-second quickstart

1. Create an inbox

curl https://threadcamp.vercel.app/v1/inboxes \
  -H "Authorization: Bearer sk_test_sandbox_threadcamp_public_demo" \
  -H "Content-Type: application/json" \
  -d '{ "display_name": "Support Agent" }'

# -> 201
# { "id": "inbox_...", "object": "inbox",
#   "address": "support-agent@in.threadcamp.com",
#   "autonomy": "auto", "created_at": "..." }

2. Send an email

curl https://threadcamp.vercel.app/v1/emails \
  -H "Authorization: Bearer sk_test_sandbox_threadcamp_public_demo" \
  -H "Content-Type: application/json" \
  -d '{
    "from": "support-agent@in.threadcamp.com",
    "to": ["you@example.com"],
    "subject": "Hello from ThreadCamp",
    "text": "Sent in one call."
  }'

# -> 201
# { "id": "msg_...", "object": "message", "status": "sent", ... }

3. Add and verify a domain

# 1. Add the domain
curl https://threadcamp.vercel.app/v1/domains \
  -H "Authorization: Bearer sk_live_..." \
  -H "Content-Type: application/json" \
  -d '{ "name": "acme-agents.email" }'

# -> 201 with dns_records: MX (receiving), TXT (spf),
#    two CNAME (dkim), TXT (dmarc). Place them at your DNS host.

# 2. Verify once the records are live
curl -X POST https://threadcamp.vercel.app/v1/domains/dom_.../verify \
  -H "Authorization: Bearer sk_live_..."

# -> { "id": "dom_...", "status": "verified", "verified_at": "..." }

Core concepts

Inbox

A real, addressable mailbox created via POST /v1/inboxes. Free inboxes live on the shared in.threadcamp.com domain (reserved - activates at launch); verified custom domains host your own. Messages are listed per inbox and filterable by direction (inbound or outbound).

Autonomy policy

Per-inbox send behaviour: auto sends immediately, approve-first holds each send for human approval, and notify sends but labels the message for a human to see.

Route + SRS

A forwarding rule (POST /v1/routes): a catch-all (*@domain) or alias match, an action of forward, webhook, inbox or split, and a destination. SRS rewrites the envelope sender so SPF and DMARC survive the forward; it defaults on for forward actions.

Domain

A custom domain added via POST /v1/domains. The response includes the MX, SPF, DKIM and DMARC records to place; POST /v1/domains/:id/verify marks it verified so you can create inboxes and send from it.

Webhook signature

Registered endpoints receive HMAC-signed deliveries. The signature is sha256(secret + "." + body), sent in the x-threadcamp-signature header. The signing secret is returned once when you create the webhook.

Keep going

API reference - every endpoint, request and response.
MCP server - use ThreadCamp as agent tools.
/openapi.json - the machine-readable spec.
/llms.txt - the agent-facing site map.

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