Expanso MCP Server

Connect a client

Streamable HTTP over POST, JSON-RPC, no authentication. Any MCP client that accepts a URL works; these are the common ones.

Claude Code

Run once in a terminal. Add --scope user to make it available in every project.

claude mcp add --transport http expanso-docs https://mcp.expanso.io/mcp

Claude (desktop and web)

Open Customize > Connectors, click the + next to Connectors, choose Custom > Web, give it a name and paste the URL. No authentication is required.

https://mcp.expanso.io/mcp

Cursor

Add to .cursor/mcp.json in a project, or ~/.cursor/mcp.json for every project.

{
  "mcpServers": {
    "expanso-docs": {
      "url": "https://mcp.expanso.io/mcp"
    }
  }
}

Codex

Run once in a terminal, or add the same server under [mcp_servers] in ~/.codex/config.toml.

codex mcp add expanso-docs --url https://mcp.expanso.io/mcp

# or in ~/.codex/config.toml
[mcp_servers.expanso-docs]
url = "https://mcp.expanso.io/mcp"

ChatGPT

Turn on Developer mode under Settings > Security and login, then create a developer-mode app from this URL. See OpenAI's developer mode guide.

https://mcp.expanso.io/mcp

Tools

What a connected client can call. This list is rendered from the server's tool registry, so it matches tools/list.

search_docsSearch Expanso documentation using semantic search. Returns relevant documentation sections for a given query.
get_resourceRetrieve the full content of a documentation resource by its URI. Use search_docs first to find relevant resources.
list_resourcesList all available documentation resources across Expanso domains. Returns URIs and descriptions.
validate_pipelineValidate an Expanso pipeline YAML configuration. Returns detailed errors with fix suggestions.
get_component_schemaGet the schema for an Expanso pipeline component including field definitions, types, defaults, and examples. Use this to understand what fields a component accepts.
get_bloblang_referenceGet Bloblang function and method reference for writing data transformations. Use this to find the correct syntax for Bloblang expressions.
suggest_pipeline_patternGet pipeline pattern suggestions based on a natural language use case description. Returns relevant examples with explanations and customization hints.
explain_errorGet detailed explanation and fix suggestions for a pipeline validation or runtime error. Transforms cryptic error messages into actionable guidance with before/after code examples.
list_componentsList available Expanso pipeline components with filtering by category, tag, or search term. Use this to discover what inputs, processors, and outputs are available.
generate_test_dataGenerate sample input data for testing a pipeline. Supports schema-based, example-based, or pipeline-analysis generation.

Search the docs

The same semantic search the search_docs tool runs, with no generation on top. Docs results link to their source; pipeline examples show their summary.