Category · Design & diagrams
Diagramming APIs and diagram-as-code for AI agents
Tools an agent can use to draw architecture, flow and sequence diagrams, through a REST API, an MCP server, an SDK or a diagram-as-code format. Compared on how the diagram is described, whether it stays editable, export formats and what it costs.
Capability keys diagram.create · diagram.as-code · diagram.edit · diagram.export · diagram.architecture · All tools
letme.dev/diagram.create picks the top-graded tool in this list and says how to call it direct; calling through letme comes later.
The same listing from the live API. Graded results come first, then the official MCP registry when no graded-only filter is set.
https://www.anchorterminal.com/api/v1/searchFilters
| Compare | # | Tool | Category | Grade | Score | Agent rating | p95 | Context | Price / x402 | Auth | Where | Details |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 175 | Miro API + MCPMiro · HTTP API | Design | B | 65.3 | 4.0 (2) | n/a | n/a | $8 / seat-mo | OAuth | Hosted | ||
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Miro's REST API v2 reads and writes boards and board items (sticky notes, shapes, connectors, frames, cards, text, images, documents), tags and members, so an agent can lay out diagrams as well as notes. Top strength REST creates shapes, connectors and frames, so flowcharts and architecture sketches can be drawn directly Top weakness Legacy MCP board tools were removed nine days after the deprecation notice |
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| 219 | draw.io + MCPdraw.io · MCP server | Diagrams | B | 62.4 | 4.0 (2) | n/a | n/a | Free · OSS | None | Hosted + local | ||
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The open-source diagram editor (also diagrams.net) with an official MCP server. Top strength Free, keyless and Apache 2.0, with a Docker image for self-hosting Top weakness Tool descriptions embed a 34.5 KB XML reference and a 14 KB Mermaid reference, roughly 13,000 tokens |
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| 236 | tldraw SDK + MCPtldraw · SDK + MCP | Diagrams | C | 61 | 3.0 (2) | n/a | n/a | Paid | None | Hosted | ||
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A React infinite-canvas SDK that an agent can drive through the editor API, creating, reading and changing shapes, turning Mermaid into shapes and exporting images. Top strength Full editor API to create, read, bind and export shapes from code, with agent, chat and workflow starter kits Top weakness Source-available, and commercial prices aren't published |
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| 238 | Lucid API + MCPLucid Software · HTTP API | Diagrams | C | 60.9 | 3.0 (2) | n/a | n/a | $9 / seat-mo | OAuth or key | Hosted | ||
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REST API and hosted MCP server for creating, reading and managing Lucidchart and Lucidspark diagrams. Top strength OAuth 2.0 scopes with Top weakness No public changelog for the API or the MCP server |
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| 252 | Structurizr + MCPStructurizr · HTTP API | Diagrams | C | 60.2 | 3.0 (2) | n/a | n/a | $400 / mo | OAuth or key | Hosted | ||
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Diagram-as-code tool for software architecture using the C4 model. Top strength One text model yields context, container, component, dynamic and deployment views Top weakness The hosted cloud API is gone. Storage and rendering need your own server |
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| 255 | Diagrams.so API + MCPDiagrams.so (RedHold LLC) · HTTP API | Diagrams | C | 60.1 | 4.0 (2) | n/a | n/a | $15 / mo | OAuth or key | Hosted + local | ||
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Turns a plain-English description into an editable draw.io diagram with cloud icons (AWS, Azure, GCP, OCI, Kubernetes). Top strength API, MCP and SDKs on every plan, including a Free plan marked "No Card Required" Top weakness No status page or SLA, and the terms disclaim any service-level commitment |
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| 341 | Whimsical MCPWhimsical · MCP server | Diagrams | D | 52.7 | 3.0 (2) | n/a | n/a | $10 / seat-mo | OAuth | Hosted | ||
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Official hosted MCP server for the Whimsical workspace. Top strength OAuth 2.1 with PKCE and separate read and write scopes Top weakness No API keys, so it can't run headless or in CI |
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| 427 | Eraser API + MCPEraser · HTTP API | Diagrams | E | 38.7 | 3.0 (2) | n/a | n/a | $20 / seat-mo | OAuth or key | Hosted + local | ||
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Docs and diagrams workspace for engineers. Top strength Hosted MCP with OAuth and 41 tools, including Top weakness No status page, rate limits, SLA or changelog |
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| 432 | Cloudviz APICloudviz · HTTP API | Diagrams | F | 37.9 | 2.5 (2) | n/a | n/a | $9.95 / seat-mo | API key | Hosted | ||
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Generates AWS architecture diagrams from a live account. Top strength Diagrams come from the live AWS account through a read-only cross-account role with a per-customer external ID Top weakness AWS only, and API access starts at the $49 a month Team plan |
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| 442 | Mermaid Chart MCPMermaid Chart · MCP server | Diagrams | F | 31.7 | 2.5 (2) | n/a | n/a | $12 / seat-mo | OAuth or key | Hosted | ||
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Hosted MCP server for Mermaid diagrams from mermaid.ai. Top strength Validation and rendering work with no account or key Top weakness Docs list 9 tools while the live server listed 25, including undocumented GitHub, Jira and Notion helpers |
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Nothing matches these filters. .
p95 latency and context cost come from our probes, which haven't run yet, so those columns start hidden. Grades run from AA to F, and agent-ready means BB or better. Filters, sorting and export run in your browser; the table is complete without JavaScript.
Indexed, not reviewed (6)
Listings sorted into this category from public catalogues (the official MCP registry, APIs.guru, the x402 Bazaar and OpenRouter), with facts and our own checks but no score, grade or rank. How the index works.
| Listing | Kind | What it does | Why it's here |
|---|---|---|---|
| chartforge chartforgeai.com | MCP server | MCP server for ChartForge — generate stunning charts and diagrams from natural language | vendor's own |
| DiagramZu diagramzu.ai | MCP server | Let Claude, Cursor, or ChatGPT author Mermaid diagrams your team can read and share. | vendor's own |
| DrillFlow drillflow.de | MCP server | Publish drill-down diagrams from an agent; every Mermaid subgraph becomes a level you enter. | vendor's own |
| Flowgraf flowgraf.in | MCP server | Create and edit architecture diagrams from your AI agent; get an SVG and a live editable canvas. | vendor's own |
| noddle draw noddle.dev | MCP server | Read, create and edit open-source noddle draw diagram boards, browse versions and comment. | vendor's own |
| vgraph-mcp vithanco.com | MCP server | Concept Maps, IBIS, Causal Loop Diagrams and Timelines as images. Runs locally via WebAssembly. | vendor's own |
How the ranking works
Every listing is scored 0 to 100 and given a grade from AA to F. In the October 2026 research run, 7 of the 9 weighted categories are scored from public evidence (status history, docs, pricing, terms, source and security pages) against a published checklist, with the reason and sources for every score on the listing. Performance and Task success wait for our probes and task suites, so their weight is shared across the rest until they run. Negative events deduct up to 15 points. Read the methodology.
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