Mermaid Lint MCP
A tool for validating Mermaid diagram syntax through CLI and MCP interfaces, providing real-time error checking and line-specific feedback. It enables AI assistants to self-validate and debug generated diagrams across all Mermaid types, ensuring valid visual documentation.
Caution. Specific findings reduced this grade. They are listed on the page. Grades reflect the full trust pyramid: code, verification depth, and reputation. New projects cap at C until adoption is earned.
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yaodebian
Source: Glama
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Install from
The grade above is for the source repository. Registries can serve a different version, so we mark the ones we were not able to read.
Disclosed vulnerabilities in this server's declared npm dependencies (via OSV). Whether each is reachable depends on the installed versions.
@modelcontextprotocol/sdk has cross-client data leak via shared server/transport instance reuse
Anthropic's MCP TypeScript SDK has a ReDoS vulnerability
Model Context Protocol (MCP) TypeScript SDK does not enable DNS rebinding protection by default
Mermaid: Improper sanitization of configuration leads to CSS injection
Mermaid: Improper sanitization of `classDef` in state diagrams leads to HTML injection
Dependencies
14 dependencies, 1 flagged: puppeteer
Tool annotations
No tools have read-only/destructive annotations
Add readOnlyHint or destructiveHint annotations to every tool so hosts can warn users before invoking.
All four hints declared on every tool
1/1 tools missing one or more hints — validate_mermaid_diagram (missing: readOnlyHint, destructiveHint, idempotentHint, openWorldHint). OpenAI's directory rejects tools where any of the four hints are missing or non-boolean.
For every tool, set all four hints (readOnlyHint, destructiveHint, idempotentHint, openWorldHint) to explicit true/false values that match the handler’s actual behaviour.
Tests pass
npm test failed — tests do not pass
Make sure npm test runs cleanly. Common cause: missing build step or missing env vars.
Production dependencies are patched
0 critical, 3 high severity in production deps — @modelcontextprotocol/sdk@1.19.1 (high), @modelcontextprotocol/sdk@1.19.1 (high)
Run npm audit fix, or upgrade the affected packages to a non-vulnerable version.
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