# MCP tools

> Every tool the MISSIN MCP server offers an AI assistant: endpoint, auth, limits, status codes, access levels and tools by area.

The hosted MCP server lets an AI assistant work in a MISSIN workspace through an API key. Every tool below maps to one public API operation, or is a task tool that chains several of them.

## Connect

Endpoint: `POST https://api.missin.co.uk/mcp` (stateless Streamable HTTP, JSON responses). Send `Authorization: Bearer sk_live_…` with a secret key; nothing else is accepted, and OAuth is not available yet (it is planned for a later phase).

Tools in the `core` toolset load by default. Add others with `?toolsets=forms,waitlists` on the URL, or `all` for every toolset.

> **Warning:**
> Loading `toolsets=all` sends about 45k tokens of tool schemas to the client, and some filter schemas are recursive, which strict clients can reject. Prefer the specific toolsets you need.

## Access levels

A key has an access level, and a tool needs that level or higher: **Read** only reads, **Write** changes workspace data, **Admin** also changes settings, connections and the brand. Tools above the key's level are left out of the tool list and refused if called by name. A tool with `destructiveHint` set removes or replaces something (an "Irreversible." summary is always destructive), so an agent must say what it will change and wait for the merchant's yes.

## When a tool needs the merchant

> **Note:**
> A result with kind `needs_choice` is a question, not an error: more than one record matched a name. The agent must ask the merchant which one they meant and call again with its id, and never guess.

## Capture costs credits

`start_capture` quotes first: call `quote_capture`, show the credits and the price, and only then call `start_capture` with the `quotedCredits` the merchant approved. The raw `DispatchPartnerCapture` and `DispatchHashtagCapture` operations spend credits directly and the balance gate is the real limit on them, so prefer `start_capture`.

## Limits and status codes

| Limit | Value |
|---|---|
| Request body | 256 KB |
| One request | 30 seconds |
| Rate | per key; over it the server answers 429 |
| Origin | A request carrying an Origin header is refused unless that origin is allowlisted; agents and servers send none |

A 504 does not cancel work already running: a write in flight may still commit after the timeout, so check with a list or get before you retry a create.

| Status | Meaning |
|---|---|
| 400 | Body is not valid JSON, or `toolsets` names one that does not exist |
| 401 | No key, a login token instead of a key, or an invalid key |
| 403 | A publishable or connection key, a refused Origin, or `insufficient_scope` when the tool needs a higher access level |
| 405 | GET and DELETE are not supported; the server is stateless |
| 413 | Body over 256 KB |
| 429 | Over the key's rate limit |
| 504 | The request took longer than 30 seconds |

Tool names are public. A 403 `insufficient_scope` on a name, against a `forbidden` tool result, tells a caller the tool exists; it does not give them access. A tool name that does not exist returns a tool result with `isError` set, not a protocol error.

## Tools by area

| Area | Tools |
|---|---|
| [Attribution](https://developer.missin.co.uk/mcp/tools/attribution.md) | 11 |
| [Campaigns](https://developer.missin.co.uk/mcp/tools/campaigns.md) | 14 |
| [Capture](https://developer.missin.co.uk/mcp/tools/capture.md) | 20 |
| [Channels](https://developer.missin.co.uk/mcp/tools/channels.md) | 6 |
| [Discounts](https://developer.missin.co.uk/mcp/tools/discounts.md) | 31 |
| [Forms](https://developer.missin.co.uk/mcp/tools/forms.md) | 26 |
| [Incentives](https://developer.missin.co.uk/mcp/tools/incentives.md) | 12 |
| [Integrations](https://developer.missin.co.uk/mcp/tools/integrations.md) | 12 |
| [Marketing](https://developer.missin.co.uk/mcp/tools/marketing.md) | 9 |
| [Orders](https://developer.missin.co.uk/mcp/tools/orders.md) | 3 |
| [Partners](https://developer.missin.co.uk/mcp/tools/partners.md) | 23 |
| [Posts](https://developer.missin.co.uk/mcp/tools/posts.md) | 16 |
| [Waitlists](https://developer.missin.co.uk/mcp/tools/waitlists.md) | 31 |
| [Workspace](https://developer.missin.co.uk/mcp/tools/workspace.md) | 15 |

Source: https://developer.missin.co.uk/mcp/tools