Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add instructions/procoders/openapi-mcp-ts/claude-mdgit clone --depth 1 https://github.com/procoders/openapi-mcp-tsWhat it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.01151 | $0.01151 |
| Opus 5 | $0.00575 | $0.00575 |
| Sonnet 5 | $0.00230 | $0.00230 |
| Haiku 4.5 | $0.00115 | $0.00115 |
Grade A, and why
openapi-mcp-ts CLAUDE.md scanned grade A with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
curl http://localhost:8080/health How it starts
The opening of the file, as written. The whole thing — 129 lines — stays where its author put it; the contents beside it link to each section on GitHub.
openapi-mcp-ts
Universal bridge between REST APIs and AI assistants via Model Context Protocol.
What It Does
Takes an OpenAPI spec or Postman Collection and exposes every endpoint as an MCP tool. Claude (or any MCP client) can then call your API directly — no custom code, no manual tool definitions.
Why It Exists
- Zero friction — Point at a spec, get MCP tools
- Format agnostic — OpenAPI 3.0/3.1, Postman v2.0/v2.1, auto-detected
- Production ready — Auth, filtering, rate limiting awareness, structured logging
- Safe defaults — DELETE disabled, tool count warnings, smart error messages
Tech Stack
| Component | Technology |
|---|---|
| Runtime | Node.js 20+ (ESM) |
| Language | TypeScript (strict mode) |
| HTTP Server | Hono |
| MCP Protocol | @modelcontextprotocol/sdk |
| CLI | Commander |
| Validation | Zod |
| OpenAPI Parsing | @apidevtools/swagger-parser |
| Postman Parsing | postman-collection |
| Logging | Pino |
Architecture
┌─────────────────┐ ┌──────────────┐ ┌─────────────────┐
│ OpenAPI/Postman │ ──▶ │ Converter │ ──▶ │ MCP Tools │
│ Spec │ │ (parser.ts) │ │ (definitions) │
└─────────────────┘ └──────────────┘ └────────┬────────┘
│
┌─────────────────┐ ┌──────────────┐ │
│ MCP Client │ ◀── │ MCP Handler │ ◀────────────┘
│ (Claude, etc) │ │ (Hono SSE) │
└─────────────────┘ └──────┬───────┘
│
┌──────▼───────┐ ┌─────────────────┐
│ Upstream │ ──▶ │ Target API │
│ Proxy │ │ │
└──────────────┘ └─────────────────┘
Project Structure
src/
├── index.ts # Entry point, server startup
├── cli.ts # CLI argument parsing (Commander)
├── config/
│ └── loader.ts # Config from CLI/env/file, Zod validation
├── converter/
│ ├── parser.ts # OpenAPI/Postman → internal format
│ ├── postman-parser.ts # Postman Collection v2.x support
│ └── tool-filter.ts # Include/exclude patterns, warnings
├── mcp/
│ ├── handler.ts # MCP protocol, tool execution
│ └── types.ts # MCP tool definitions
├── server/
│ ├── routes.ts # /health, /tools, /mcp endpoints
│ └── upstream.ts # Proxy requests to target API
└── utils/
└── logger.ts # Pino logger setup
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 2d ago First seen · 129 lines · 1,151 tokens per session scan A 3a5bc188dbb8
openapi-mcp-ts CLAUDE.md is an instructions file published in the GitHub repository procoders/openapi-mcp-ts (0 stars, last pushed 8mo ago), licensed Apache-2.0. It adds 1,151 tokens to every session, about $0.0058 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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