# outline_diagram

> Page: https://docs.plotwork.dev/mcp/tools/outline-diagram. Index of every page: https://docs.plotwork.dev/llms.txt

Describe valid diagram source as plain text: participants, steps, tables, and connections in reading order, to check the diagram says what you meant or to use as alt text. It is a single tool of the MCP server and the HTTP API, with the title "Outline diagram".

## TL;DR

| Question | Answer |
|---|---|
| What is it? | A single tool: it does one thing. |
| What does it do? | Describe valid diagram source as plain text: participants, steps, tables, and connections in reading order, to check the diagram says what you meant or to use as alt text. |
| How do I call it over HTTP? | [`POST /v1/diagrams/outline`](https://docs.plotwork.dev/api/post-v1-diagrams-outline.md) |
| Does it change anything? | No. It is read-only and idempotent, and it talks to nothing outside itself. It saves no file and returns its answer as data. |
| Which bounds apply? | None beyond the limits of each argument, which are in the schema below. |
| Where do I read its schema as data? | An MCP client gets the name, description, and JSON Schema of every tool from `tools/list`. |

## What it does

Describe valid diagram source as plain text: participants, steps, tables, and connections in reading order, to check the diagram says what you meant or to use as alt text. Source with errors fails with diagnostics. Does not render. Prefer draw_diagram, which returns the outline with the check and the pictures.

## Arguments

| Field | Type | Required | Description |
|---|---|---|---|
| `source` | `string` | yes | Diagram source; the first line is the header, such as flow "Title" (draw_diagram lists every kind). at least 1 character; at most 50000 characters. |
| `settings` | `object` | no | The repo's plotwork.config.json, if any. Schema: https://docs.plotwork.dev/schemas/plotwork.config.json. |

## Result

| Field | Type | Required | Description |
|---|---|---|---|
| `kind` | `string` | yes | A diagram kind: flow, sequence, schema, git, gantt, class, state, timeline, journey, mindmap, treemap, pie, quadrant, layers, c4, matrix, sankey, xychart, tree, or swimlane today. Later versions add kinds, so expect others. |
| `summary` | `string` | yes | One-line description. |
| `outline` | `string[]` | yes | Lines in reading order: participants, steps, tables, and connections. |

## Behavior hints

| Hint | Value |
|---|---|
| `readOnlyHint` | true |
| `destructiveHint` | false |
| `idempotentHint` | true |
| `openWorldHint` | false |

## See also

| Doc | Why |
|---|---|
| [Tool reference](https://docs.plotwork.dev/mcp/tools.md) | Every tool, with the workflows first |
| [`POST /v1/diagrams/outline`](https://docs.plotwork.dev/api/post-v1-diagrams-outline.md) | The same operation over HTTP |
| [Language reference](https://docs.plotwork.dev/reference/language.md) | What the diagram source may contain |
| [Writing diagrams with an agent](https://docs.plotwork.dev/mcp/agent-loop.md) | The loop in practice |