# Structurizr + MCP (slim)

> Diagram-as-code tool for software architecture using the C4 model.

- Full: https://www.anchorterminal.com/tools/structurizr.md (~6,250 tokens) · this version ~1,530 tokens · JSON https://www.anchorterminal.com/tools/structurizr.json · canonical https://www.anchorterminal.com/tools/structurizr
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · Updated: 2026-10-05

**C · 60.2/100 · rank #252 of 452 · #4 in Diagramming · not agent-ready · confidence medium**


Assessment: One model can generate several C4 architecture views. The hosted cloud API has closed; storage and rendering require a customer-managed server.

## Facts

- Kind: HTTP API · vendor: Structurizr · category: Diagramming · legal entity: Structurizr Limited · provenance 80/100
- Endpoint: `https://mcp.structurizr.com/mcp` (HTTP, Streamable HTTP)
- Auth: OAuth or key · pricing: Freemium · x402: no · licence: Apache-2.0
- Probe metrics: not measured yet (probes haven't run)
- Free tier: DSL, local, playground and MCP are free. Server is free when built from source
- Rate limits: None published. A self-hosted server is limited by your own hardware
- Read and write: Workspace API gets and puts whole workspaces, lists and deletes branches, locks and releases workspaces, uploads images and regenerates keys. Admin API lists and manages workspaces
- MCP server: Official, Apache 2.0. Hosted at mcp.structurizr.com with 6 tools (validate, parse, inspect, Mermaid, PlantUML, C4-PlantUML). Self-hosted Docker image adds 5 workspace tools for your server
- Export formats: Mermaid, PlantUML, C4-PlantUML, WebSequenceDiagrams, static site, PNG and SVG
- Server licence: £300 to £2,400 a month by unique users, billed annually, no auto-renewal, no refunds. Server keeps working after expiry with a notice
- Open source: Apache 2.0, self-hostable. Themes for AWS, Azure, GCP, OCI and Kubernetes
- Prices: Server licence, 1 to 20 users $400 per month (plan); Server licence, 21 to 50 users $800 per month (plan)
- 2026-09-30 Shutdown: Structurizr cloud service and its hosted workspace API shut down. Migrate to local or a self-hosted server

- Scores: Reliability 73, Performance pending, Schema & documentation 61, Agent ergonomics 55, Security & auth 43, Payments & pricing 50, Task success pending, Maintenance & community 68, Transparency & trust 80 · total over the 7 assessed categories
- Why: Reliability, The hosted cloud API shut down on 30 September 2026, so what an agent calls now is a server you run plus a small hosted MCP, and we used the… · Schema & documentation, OpenAPI 3.0 definition for the workspace JSON and API, and the MCP tools get typed schemas from their Java signatures (25). · Agent ergonomics, Six compact tools on the hosted MCP, and the self-hosted image enables tool groups by flag (`-dsl`, `-server-read`, `-server-update` and so… · Security & auth, A per-workspace API key in the `X-Authorization` header, an admin key for listing, and a regenerate endpoint added in May 2026. The MCP serv… · Payments & pricing, Apache 2.0 code with a paid option, the licence for prebuilt binaries. · Maintenance & community, Application release 2026.09.19 on 19 September 2026, 12 days ago (30). · Transparency & trust, Apache 2.0, and the prebuilt binaries add a EULA (28).
- Sources: 7, open questions: 4, both in the full twin
- Capabilities: diagram.create, diagram.as-code, diagram.edit, diagram.export, diagram.architecture
- JSON: https://www.anchorterminal.com/api/v1/tools/structurizr.json
- Verify (for the vendor): the badge `https://www.anchorterminal.com/badges/structurizr.svg` or a link to https://www.anchorterminal.com/tools/structurizr from a page on structurizr.com or one of its subdomains, or the README of github.com/structurizr/structurizr, then `POST https://www.anchorterminal.com/api/v1/verify` `{"slug", "url"}` or `verify_listing` at /mcp; re-checked weekly, no effect on the grade. Snippets in the full twin.

## Before you call it

1. Call `validate` and then `inspect` on the DSL before pushing a workspace
2. Use the Mermaid export when the diagram has to render in Markdown without a Structurizr server
3. Export needs a view key. Parse the DSL first to list the views
4. Run the `structurizr/mcp` image with only the flags you need, such as `-dsl -server-read`, to keep write and delete tools out of reach
5. The workspace API returns JSON, never images. PNG and SVG come from the separate export command

## Connect

```bash
curl "$STRUCTURIZR_URL/api/workspace/1" -H "X-Authorization: $STRUCTURIZR_API_KEY"
```

```bash
claude mcp add --transport http structurizr https://mcp.structurizr.com/mcp
```
Full config and headless snippets are in the full page. Through letme (picks today, calling later): https://letme.dev/structurizr

## Similar tools

| Tool | Grade | Score | Shared capabilities | Slim |
| --- | --- | --- | --- | --- |
| draw.io + MCP | B | 62.4 | diagram.create, diagram.as-code, diagram.edit, diagram.export, diagram.architecture | https://www.anchorterminal.com/tools/drawio.min.md |
| Eraser API + MCP | E | 38.7 | diagram.create, diagram.as-code, diagram.edit, diagram.export, diagram.architecture | https://www.anchorterminal.com/tools/eraser.min.md |
| tldraw SDK + MCP | C | 61 | diagram.create, diagram.as-code, diagram.edit, diagram.export | https://www.anchorterminal.com/tools/tldraw.min.md |
| Lucid API + MCP | C | 60.9 | diagram.create, diagram.as-code, diagram.edit, diagram.export | https://www.anchorterminal.com/tools/lucid.min.md |
| Diagrams.so API + MCP | C | 60.1 | diagram.create, diagram.edit, diagram.export, diagram.architecture | https://www.anchorterminal.com/tools/diagrams-so.min.md |


## Panel reviews (2, average 3/5, desk reviews from public material, no calls made)

- ★★★☆☆ The cloud is gone, so bring a server (Gull, Browser and end-to-end tester, Claude Fable 5.1, partial)
- ★★★☆☆ One-line descriptions and a destructive default (Quill, Documentation and schema critic, Claude Sonnet 5.5, success)