# describe

URL: https://docs.hanzo.ai/docs/mcp-tools/unmapped/describe

> The description and input schema of ONE operation, named as it appears in a subsystem tool's "op" enum.

The description and input schema of ONE operation, named as it appears in a subsystem tool's "op" enum. Read it before filling "input".

|               |                               |
| ------------- | ----------------------------- |
| **Tool**      | `describe`                    |
| **Address**   | `https://api.hanzo.ai/v1/mcp` |
| **Method**    | `tools/call` (JSON-RPC 2.0)   |
| **Arguments** | 1, 1 required                 |
| **Operation** | none in the OpenAPI document  |
| **Product**   | —                             |

## Arguments

| Field | Type     | Required | Default | Values | Description |
| ----- | -------- | -------- | ------- | ------ | ----------- |
| `op`  | `string` | **yes**  | —       | —      | —           |

`tools/list` declares a type and which fields are required for each field and nothing further, and the OpenAPI document describes no operation for this tool. A `—` above means neither source constrains the field, not that it is unconstrained in practice.

## Call it

A `tools/call` carries every argument in one flat object — nothing binds to a path or a query string. This call carries exactly the arguments the operation requires, so it is the smallest one that can run.

```bash
curl -X POST https://api.hanzo.ai/v1/mcp \
  -H "Authorization: Bearer $HANZO_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
       "jsonrpc": "2.0",
       "id": 1,
       "method": "tools/call",
       "params": {
         "name": "describe",
         "arguments": {
           "op": "<op>"
         }
       }
     }'
```

Values are the operation's own defaults and enumerated values where it declares them, and a `<placeholder>` where neither source declares one. `tools/list` needs no credential; `tools/call` does — called without one MCP answers HTTP 200 with a JSON-RPC result whose `isError` is set and whose text says what was missing. [How to get a key →](https://docs.hanzo.ai/docs/mcp-tools#credentials)

## The operation behind it

MCP exposes `describe`, but the copy of the OpenAPI document this build holds (pinned at `e2d5eae3c`) describes no operation for it — neither under that name nor at the route the name implies. That is either a route the document has yet to declare, or one MCP has renamed since the pin. Everything on this page comes from `tools/list`; there is no REST reference to link to until the two agree.

---

[All 120 tools](https://docs.hanzo.ai/docs/mcp-tools/all-tools) · [MCP](https://docs.hanzo.ai/docs/mcp-tools) · [API reference](https://docs.hanzo.ai/docs/openapi)

Generated from `tools/list` on `https://api.hanzo.ai/v1/mcp` — 120 tools captured 2026-09-30.