@cyanheads/oecd-mcp-server
Search, explore, and query 1,500+ OECD statistical datasets (national accounts, employment, trade, education, health) from the OECD SDMX API via MCP. STDIO or Streamable HTTP.
Public Hosted Server: https://oecd.caseyjhand.com/mcp
Overview
OECD statistics across 1,500+ datasets on national accounts, employment, trade, education, and health. Search datasets, inspect their dimensions, query observations, and run SQL over large multi-country time series. No API key required.
Tools
Five discovery and data tools plus three DataCanvas tools for large query results:
| Tool | Description |
|---|---|
oecd_list_agencies | List OECD SDMX agencies with their directorate and the number of dataflows each publishes |
oecd_search_datasets | Search 1,500+ OECD dataflows by keyword or theme |
oecd_get_dataset_info | Fetch a dataflow's dimensions, key order, and codelist references |
oecd_get_dimension_values | Fetch valid codes and labels for one dimension (countries, measures, frequencies) |
oecd_query_dataset | Fetch observations filtered by dimension key and time range; spills large results to DataCanvas |
oecd_dataframe_describe | List DataCanvas tables and columns staged by a prior oecd_query_dataset spill |
oecd_dataframe_query | Run a read-only SQL SELECT against DataCanvas tables |
oecd_dataframe_drop | Drop a staged DataCanvas table or view once the analysis is done — opt-in via OECD_DATAFRAME_DROP_ENABLED=true |
Resources
| Resource | Description |
|---|---|
oecd://dataflow/{agency_id}/{flow_id} | Dimension metadata for a single OECD dataflow — same content as oecd_get_dataset_info |
All resource data is also reachable via tools. Use oecd_get_dataset_info for the same content.
Capability reference
oecd_list_agencies tool
- No inputs; returns every agency ID (e.g.
OECD.SDD.NAD) with its directorate name and dataflow count, sorted by count - Publishers outside OECD that ship dataflows through the same catalog (
ESTAT,IAEG-SDGs) carry no directorate
oecd_search_datasets tool
querytoken-matched across dataflow names and descriptions; optionalagency_idscope;limit(1–100) andoffsetpaging withtotal_matches- Each result carries its
flow_ref— the identifier every other tool takes — andmatched_in(name,description, orboth)
oecd_get_dataset_info tool
- Takes a
flow_ref; returns every dimension in key order with its concept name and codelist reference, plus akey_exampleforoecd_query_dataset - Fails
invalid_flow_reffor a string that is not a flow reference anddataflow_not_foundfor one OECD does not publish
oecd_get_dimension_values tool
- Takes a
flow_refanddimension_id; optionalquerysubstring-matches both code and label limit(1–500, default 50) andoffsetpage the matches, with the full match count when more remain
oecd_query_dataset tool
flow_refplus a dot-delimitedkey(+for multiple values, empty segments as wildcards) and optionalstart_period/end_period- One row per observation with every dimension and attribute as its own column;
valueis pre-multiplied byvalue_scale - Large results spill to DataCanvas with
truncated: true,canvas_id, andtable_name; without a canvas every row stays instructuredContentand only the rendered table is capped (content_table_capped) - A spill includes a
noticenaming the canvas and table: inspect columns withoecd_dataframe_describe, then useoecd_dataframe_queryfor SQL over the full result. Fitting results allocate no new canvas; an explicitcanvas_idis still validated.
oecd_dataframe_describe tool
- Takes the
canvas_idoecd_query_datasetreturned; lists each staged table and view with its row count and column names and types
oecd_dataframe_query tool
canvas_idplus one read-only SQLSELECT; writes, DDL, and system-catalog access are rejected- Returns rows capped at the canvas row limit, with
row_countreporting the full count
oecd_dataframe_drop tool
canvas_idplus atable_nameasoecd_dataframe_describelists it; returns the dropped object'skindand theremaining_tables- Opt-in: listed but not callable unless
OECD_DATAFRAME_DROP_ENABLED=true
oecd://dataflow/{agency_id}/{flow_id} resource
- Same content as
oecd_get_dataset_info, asapplication/json {flow_id}is{dsd_id}@{df_id}with@encoded as%40(e.g.oecd://dataflow/OECD.SDD.NAD/DSD_NAAG%40DF_NAAG_I), or the bare{df_id}
Features
Built on @cyanheads/mcp-ts-core: stdio and Streamable HTTP transports, pluggable auth (none / jwt / oauth), swappable storage (in-memory, filesystem, Supabase, Cloudflare KV/R2/D1), structured logging with optional OpenTelemetry tracing.
OECD-specific:
- Keyless access — no API key required; OECD SDMX 2.1 REST API is fully public
- Covers 1,500+ dataflows across 20+ OECD statistical departments (national accounts, employment, inflation, trade, education, health, environment, taxation, inequality)
- Delegated dataflows and codelist revisions resolved end to end — a dataflow OECD catalogues on one service root but defines on another follows the catalog's own link for structure, codes, and observations, and codes come from the revision the datastructure names rather than the endpoint's current latest
AllDimensionsobservation mode — one-pass SDMX-JSON decoding into flat row objects, no nested series key reconstructionoecd_query_datasetmaterializes large observation sets (multi-country time-series) on a DuckDB DataCanvas for in-conversation SQL analytics; the threeoecd_dataframe_*tools work on it and needCANVAS_PROVIDER_TYPE=duckdb
Agent-friendly output:
- Workflow-aware tool surface —
flow_reffrom search flows directly into info, values, and query tools without reconstruction - Spill signaling —
truncated: true+canvas_idtells the agent to switch to SQL instead of parsing a truncated inline list - Full SDMX decoding server-side — agents see
{ REF_AREA: "United States", MEASURE: "Gross domestic product", UNIT_MULT: "Billions", value: 26054614000000, value_scale: 1000000000 }, not raw index arrays
Getting started
Public Hosted Instance
A public instance is available at https://oecd.caseyjhand.com/mcp — no installation required. It serves Streamable HTTP; each client takes its own config shape.
For Claude Code:
claude mcp add --transport http oecd-mcp-server https://oecd.caseyjhand.com/mcp
For Cline (cline_mcp_settings.json):
{
"mcpServers": {
"oecd-mcp-server": {
"type": "streamableHttp",
"url": "https://oecd.caseyjhand.com/mcp"
}
}
}
For Cursor (mcp.json):
{
"mcpServers": {
"oecd-mcp-server": {
"url": "https://oecd.caseyjhand.com/mcp"
}
}
}
Claude Desktop adds remote servers under Settings → Connectors.
Self-Hosted / Local
Add the following to your MCP client configuration file.
{
"mcpServers": {
"oecd-mcp-server": {
"type": "stdio",
"command": "bunx",
"args": ["@cyanheads/oecd-mcp-server@latest"],
"env": {
"MCP_TRANSPORT_TYPE": "stdio",
"MCP_LOG_LEVEL": "info"
}
}
}
}
Or with npx (no Bun required):
{
"mcpServers": {
"oecd-mcp-server": {
"type": "stdio",
"command": "npx",
"args": ["-y", "@cyanheads/oecd-mcp-server@latest"],
"env": {
"MCP_TRANSPORT_TYPE": "stdio",
"MCP_LOG_LEVEL": "info"
}
}
}
}
Or with Docker:
{
"mcpServers": {
"oecd-mcp-server": {
"type": "stdio",
"command": "docker",
"args": [
"run", "-i", "--rm",
"-e", "MCP_TRANSPORT_TYPE=stdio",
"ghcr.io/cyanheads/oecd-mcp-server:latest"
]
}
}
}
DataCanvas SQL analytics for large query results is on by default. To turn it off, add CANVAS_PROVIDER_TYPE=none:
{
"mcpServers": {
"oecd-mcp-server": {
"type": "stdio",
"command": "bunx",
"args": ["@cyanheads/oecd-mcp-server@latest"],
"env": {
"MCP_TRANSPORT_TYPE": "stdio",
"CANVAS_PROVIDER_TYPE": "none"
}
}
}
}
For Streamable HTTP, set the transport and start the server:
MCP_TRANSPORT_TYPE=http MCP_HTTP_PORT=3010 bun run start:http
# Server listens at http://localhost:3010/mcp
Prerequisites
- Bun v1.4.0 or higher (or Node.js v24+).
- No API key required — OECD SDMX is a free, public API.
Installation
- Clone the repository:
git clone https://github.com/cyanheads/oecd-mcp-server.git
- Navigate into the directory:
cd oecd-mcp-server
- Install dependencies:
bun install
- Configure environment:
cp .env.example .env
# edit .env — most vars are optional; no API key required
Configuration
All configuration is validated at startup via Zod schemas in src/config/server-config.ts. Key environment variables:
| Variable | Description | Default |
|---|---|---|
OECD_BASE_URL | OECD SDMX REST API base URL. Must be an https origin that answers directly — no redirect is followed, so a plaintext http:// origin fails instead of being upgraded to https. | https://sdmx.oecd.org/public/rest |
OECD_TIMEOUT_MS | Per-request timeout in milliseconds. | 30000 |
CANVAS_PROVIDER_TYPE | Canvas engine. With duckdb, a large oecd_query_dataset result spills to a queryable table instead of just capping the rendered preview; with none, every row still comes back in structuredContent and only the rendered table is capped. | duckdb |
OECD_DATAFRAME_DROP_ENABLED | Set to true to register oecd_dataframe_drop. Off, the tool is listed as disabled and clients cannot call it. | false |
MCP_TRANSPORT_TYPE | Transport: stdio or http. | stdio |
MCP_HTTP_PORT | Port for HTTP server. | 3010 |
MCP_SESSION_MODE | HTTP session posture: stateful, stateless, or auto. The server declares stateless in source — it keeps no per-session state, and a DataCanvas handle is keyed by canvas_id — so set this only to override that. | stateless |
MCP_AUTH_MODE | Auth mode: none, jwt, or oauth. | none |
MCP_LOG_LEVEL | Log level (RFC 5424). | info |
LOGS_DIR | Directory for log files (Node.js only). | <project-root>/logs |
LOG_TOOL_FAILURE_PAYLOADS | Log each failed tool call's arguments and result, redacted by key name and capped at LOG_TOOL_FAILURE_PAYLOAD_MAX_BYTES (default 16384). A secret inside a free-form value is not redacted. | false |
OTEL_ENABLED | Enable OpenTelemetry instrumentation. | false |
See .env.example for the full list of optional overrides.
Running the server
Local development
-
Build and run:
# One-time build bun run rebuild # Run the built server bun run start:stdio # or bun run start:http -
Run checks and tests:
bun run devcheck # Lint, format, typecheck, security bun run test # Vitest test suite bun run lint:mcp # Validate MCP definitions against spec
Docker
docker build -t oecd-mcp-server .
docker run --rm -p 3010:3010 oecd-mcp-server
The Dockerfile defaults to HTTP transport, stateless session mode, and logs to /var/log/oecd-mcp-server. OpenTelemetry peer dependencies are installed by default — build with --build-arg OTEL_ENABLED=false to omit them.
Project structure
| Directory | Purpose |
|---|---|
src/index.ts | createApp() entry point — registers tools/resources and initializes services. |
src/config/ | Server-specific environment variable parsing and validation with Zod. |
src/mcp-server/tools/definitions/ | Tool definitions (*.tool.ts) — eight tools for OECD data discovery, retrieval, and DataCanvas analysis. |
src/mcp-server/resources/definitions/ | Resource definitions (*.resource.ts) — the oecd://dataflow resource. |
src/services/oecd-http/ | Shared OECD fetch boundary — timeout and retry-classification corrections used by both services below, the origin check every delegated service root passes before it is addressed, the refusal of any redirect off the configured host, and the classification that gives an upstream refusal the same declared reason on every tool and resource. |
src/services/oecd-structure/ | OECD SDMX structure service — dataflows, data structures, codelists. |
src/services/oecd-data/ | OECD SDMX data service — observations, SDMX-JSON decoding, DataCanvas spillover. |
src/services/canvas-accessor/ | DataCanvas accessor — registers and exposes the framework canvas instance to tools. |
tests/ | Unit and integration tests mirroring src/. |
Development guide
See CLAUDE.md for development guidelines and architectural rules. The short version:
- Handlers throw, framework catches — no
try/catchin tool logic - Use
ctx.logfor request-scoped logging,ctx.statefor tenant-scoped storage - Register new tools and resources via the barrels in
src/mcp-server/*/index.ts - Wrap external API calls: validate raw SDMX-JSON → normalize to domain type → return output schema; never fabricate missing fields
Contributing
Issues are welcome — see CONTRIBUTING.md for what makes one actionable, and CODE_OF_CONDUCT.md for how we work together. Run checks and tests before submitting:
bun run devcheck
bun run test
License
Apache-2.0 — see LICENSE for details.