Smithery.ai MCP Directory API
Smithery.ai is the largest public directory and hosting platform for MCP servers — 7,300+ servers with semantic search, hosted deployment, and an API for discovering and running MCP servers programmatically.
Score Breakdown
⚙ Agent Friendliness
🔒 Security
Credentials for individual MCP servers passed through Smithery's runtime — trust model depends on their infrastructure security. No audit trail for hosted server executions. Use caution with sensitive credentials.
⚡ Reliability
Best When
Your agent needs to discover what MCP tools are available for a given task at runtime. Smithery's semantic search lets agents find tools they weren't configured with at startup.
Avoid When
You need certified quality ratings (Smithery is a directory, not a quality rating platform — use Assay for that). Or if you need private tool catalogs.
Use Cases
- • Discovering MCP servers by capability/category via semantic search API
- • Running MCP servers on-demand without local setup via Smithery's hosted runtime
- • Fetching MCP server metadata (tools, resources, prompts) before connecting
- • Building agent workflows that dynamically discover and invoke MCP servers
- • Browsing and comparing MCP server capabilities across thousands of packages
Not For
- • Production workloads requiring SLA guarantees (Smithery is best-effort for free tier)
- • Private or self-hosted MCP servers (Smithery is a public directory)
- • Non-MCP tool registries (only covers Model Context Protocol servers)
Interface
Authentication
API key from smithery.ai account. Free tier available for discovery/search. Hosted server execution may require additional auth per-server (server-specific credentials passed at runtime).
Pricing
Free tier covers discovery and browsing. Hosted server execution credits may be required. Pricing evolving as platform matures.
Agent Metadata
Known Gotchas
- ⚠ MCP server quality on Smithery varies enormously — directory has both excellent and broken servers
- ⚠ Hosted execution latency is higher than local MCP servers — expect 500ms-2s round-trips
- ⚠ Some servers require credentials that must be passed at connection time — discovery doesn't always list these requirements clearly
- ⚠ Server count (7,300+) sounds impressive but many are experimental or abandoned
- ⚠ Smithery's own quality ratings are basic compared to Assay's multi-dimensional scoring
Alternatives
Full Evaluation Report
Detailed scoring breakdown, competitive positioning, security analysis, and improvement recommendations for Smithery.ai MCP Directory API.
Scores are editorial opinions as of 2026-03-06.