@cyanheads/earthquake-mcp-server
Search USGS and EMSC seismic data — real-time feeds, event queries, and earthquake counts via MCP. STDIO or Streamable HTTP.
4 Tools • 3 Resources
Overview
Seismic data from USGS ComCat and the EMSC SeismicPortal. Fetch real-time earthquake feeds, search and count seismic events by time, magnitude, depth, and location, and pull full analysis detail for a single event.
Tools
Resources
Skill
Capability reference
earthquake_get_feed tool
- Choose a magnitude tier (
all, 1.0, 2.5, 4.5, significant) and a window (hour, day, week, month). USGS caches these feeds; use earthquake_search_events for historical or filtered queries.
- Returns events, page count, generation time, and source feed URL.
all includes microseisms; significant is USGS-curated using magnitude, felt reports, and PAGER impact.
- Each page returns
limit events (default 15), fewer only on the last page. A limit above 1,000 returns 1,000 with a notice naming the requested and applied values; with EARTHQUAKE_CLAMP_LIMITS=false it is rejected instead. limit applies to the first page; later pages keep the page size in the cursor. totalCount reports the whole feed; pass nextCursor back unchanged with the same tier and window.
- Continuations read the first-read generation, unaffected by upstream edits. Retention lasts up to 15 minutes, subject to capacity eviction and restart.
cursor_expired means restart without a cursor; legacy cursors must also be restarted.
earthquake_search_events tool
- Search
usgs or emsc by time, magnitude, depth, radius, or bounding box. A radius requires latitude, longitude, and radius_km together; box edges are independently optional, support antimeridian bounds up to ±360°, and intersect a supplied circle.
- Returns normalized events with
event_type, EMSC's event_certainty, and USGS's associated_ids (other network IDs merged into the event). ignoredFilters names unsupported filters; queryEcho reports the effective query.
- Both search and count accept open
magnitude_type values on either source; EMSC matches its own lowercase types (mb, mw) exactly and has no mww. product_type (required product, e.g. moment-tensor) and review_status (automatic or reviewed) apply only to USGS; EMSC names them in ignoredFilters. Blank values mean omitted.
event_type, magnitude_type, and product_type stay open strings; USGS matches them case-insensitively, and event_type takes a comma-separated list. USGS answers a value outside its published vocabulary with zero events, so when a USGS search's first page or a USGS count comes back empty, notice names each unlisted value and the listed values it equals once case and -, _, and spaces are ignored: product_type "moment_tensor" suggests "moment-tensor". The vocabulary read is one attempt within the call's deadline, cached for 24 hours; if it fails, the zero returns as it would without the check. EMSC publishes no vocabulary and is not checked.
min_mmi (ShakeMap intensity, Modified Mercalli) and min_cdi (DYFI community intensity), each 1–12, select events by how strongly they shook, which a magnitude floor or alert_level misses. Both apply only to USGS: an event without a ShakeMap or DYFI reports never matches, and EMSC names them in ignoredFilters.
- Date-only bounds (including expanded year/year-month forms) mean midnight at the start of the named day on both sources:
2026-10-10 becomes 2026-10-10T00:00:00. Explicit time and timezone suffixes are preserved; unpadded date components are padded. Offsetless times use UTC for the 30-day default. queryEcho shows the exact effective bounds.
- Sort by time or magnitude in either direction. Each call requests
limit events upstream (default 15, set by DEFAULT_LIMIT) and returns them all, fewer only on the last page. A limit above 1,000 returns 1,000 with a notice naming the requested and applied values; with EARTHQUAKE_CLAMP_LIMITS=false it is rejected instead. queryEcho.limit reports the applied limit. Continue with the returned nextOffset (offset plus the events returned, counting from 1) and the same filters, limit, and order. Search pages read the current catalog, so upstream edits can affect later pages.
- Strictly inverted magnitude, depth, or explicit time bounds fail locally as
invalid_range, naming both values and recovery. Equal and single bounds remain valid; time comparisons use UTC instants, including explicit offsets. Calendar-invalid values remain for upstream rejection.
- A nonempty short page establishes
totalCount; an empty first page establishes zero, while an empty later page leaves the total unknown. Full pages use a count lookup, with countUnavailable on failure. Feed, search, count, and event calls each share one 50-second deadline across their requests and retries; for search that includes the count lookup. Cancellation remains cancellation.
earthquake_count_events tool
- Count matches using the same filters as
earthquake_search_events, without fetching events. Omit start_time for the last 30 days; queryEcho reports the resolved window and applied filters.
exceeds_limit flags the 20,000-event single-request threshold, not a retrieval ceiling: search offset paging can retrieve larger match sets. max_allowed is 20,000 for USGS and null for EMSC; ignoredFilters names filters the source cannot apply.
- A USGS count of zero carries
notice when a supplied event_type, magnitude_type, or product_type value is not in the USGS vocabulary, as search's empty first page does.
earthquake_get_event tool
-
Pass the id of any feed or search result. An EMSC unid from a source=emsc search (eight digits, underscore, seven digits, e.g. 20190706_0000043) is looked up on EMSC SeismicPortal; every other ID goes to USGS (e.g. us6000sznj).
-
A USGS event returns the normalized event plus optional detail: PAGER, ShakeMap, DYFI, moment tensor, ground-failure alerts, origin quality (including depth_type, which separates an assigned depth from a located one), and finite-fault dimensions. Groups are omitted when none of their projected fields is available; absence does not imply zero impact. associated_ids lists the other network IDs USGS holds for the event; an alias such as us70004bn0 returns the preferred event (ci38457511) with the alias listed there.
-
An EMSC event returns the same normalized event its search result carries, with no detail and no associated_ids.
-
include opts into more for USGS events:
-
A requested group that is not returned is listed in unavailable_includes: not_published when the event has no such product (every group on an EMSC event) or its product lacks the files the group reads (PAGER products published before the JSON files existed), fetch_failed when the download failed, returned HTML, did not parse, pointed outside the configured USGS origin, or answered with a redirect. The event, detail, and other groups still return; cancellation propagates. The event request and its product downloads share one 50-second deadline.
-
Blank IDs fail locally; canonical IDs and aliases match case-insensitively. ShakeMap includes the producer's code_version when published.
earthquake://feed/{magnitude_tier}/{time_window} resource
- Choose the same magnitude tiers and time windows as
earthquake_get_feed; all 20 combinations are listed as browsable resources.
- Returns 100 events per
application/json page in the compact event projection, plus totalCount, truncated, nextCursor, and next_uri. Read next_uri verbatim until it is absent. The continuation URI is earthquake://feed/{magnitude_tier}/{time_window}/page/{cursor}.
- Feed resources share retained generations with
earthquake_get_feed. Cache hints are private with zero lifetime because continuation tokens belong to the requesting tenant. Upstream failures classified as ServiceUnavailable expose feed_unavailable; those classified as Timeout expose feed_timeout, each with recovery guidance and no captured upstream body. Availability failures preserve numeric HTTP status; HTTP 501 remains non-retryable and points to EMSC search. Other error classes propagate unchanged.
earthquake://event/{event_id} resource
- Pass a USGS or EMSC
event_id from a feed or search result. Returns the same event and optional detail products as earthquake_get_event; it takes no include.
- Uses that tool's
event_deleted, not_found, source_unavailable, and source_timeout error contract.
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.
USGS/EMSC-specific:
- Type-safe clients for the USGS FDSN/GeoJSON API and the EMSC FDSN-WS API, normalizing both into one shared earthquake domain schema
- Automatic retry with backoff and per-request timeouts on every upstream call; detects USGS's rate-limited/CDN failure mode (HTML served instead of GeoJSON) and maps it to a typed service-unavailable error instead of parsing it as data. A body that is not the expected document fails the same way without a retry, and a connection dropped mid-body is retried; neither passes parser or runtime text to the caller
- EMSC's two-character
evtype code is decoded against the published event-type/certainty nomenclature into the same vocabulary USGS publishes, so event_type carries one meaning across both sources
- USGS-only filters (
alert_level, min_felt, min_significance, min_mmi, min_cdi, event_type, product_type, review_status) are named in ignoredFilters when source=emsc. On USGS, event_type="earthquake" excludes quarry blasts and other non-tectonic records.
- No API key or rate-limit tier required — both USGS and EMSC are fully public, keyless APIs
Agent-friendly output:
- Provenance —
source: "usgs" | "emsc" on search and count responses, plus source_catalog/auth fields naming the catalog and authoritative agency, so agents can weigh two independent solutions against each other
- Discriminated output contracts —
event_type and EMSC's event_certainty preserve published classifications, with absent fields remaining unknown; exceeds_limit, countUnavailable, and truncated flags let callers branch on data instead of parsing prose
- Response shaping — fields a source does not publish come back
null, never a fabricated zero (tsunami, status, and mmi are always null on EMSC events); USGS-only filters dropped for an EMSC query are named in ignoredFilters rather than silently ignored
- Graceful degradation — an upstream rejection surfaces the service's own explanation (offending parameter, accepted format) in the error message instead of a bare status code, a failed follow-up count degrades to
countUnavailable rather than failing the whole search, and a failed product download lists its include groups as fetch_failed rather than failing the event lookup
Getting started
Public Hosted Instance
A public instance is available at https://earthquake.caseyjhand.com/mcp — no installation required. Point any MCP client at it via Streamable HTTP:
Self-Hosted / Local
Add the following to your MCP client configuration file.
Or with npx (no Bun required):
Or with Docker:
For Streamable HTTP, set the transport and start the server:
Prerequisites
- Bun v1.4.0 or higher.
- No API keys required — USGS and EMSC data is fully public.
Installation
- Clone the repository:
- Navigate into the directory:
- Install dependencies:
Configuration
All configuration is validated at startup via Zod schemas in src/config/server-config.ts. Key environment variables:
Empty values and unsubstituted whole-value ${…} placeholders use the defaults. See .env.example for optional overrides.
Running the server
Local development
Docker
The Dockerfile defaults to HTTP transport, stateless session mode, and logs to /var/log/earthquake-mcp-server. OpenTelemetry peer dependencies are installed by default — build with --build-arg OTEL_ENABLED=false to omit them.
Project structure
Development guide
See CLAUDE.md for development guidelines and architectural rules. The short version:
- Handlers throw, framework catches — no
try/catch in tool logic
- Use
ctx.log for logging, ctx.state for storage
- Register new tools and resources in the
createApp() arrays
- Validate upstream data, normalize to domain types, and preserve missing values rather than inventing facts
Contributing
Issues are welcome. Run checks and tests before submitting:
License
This project is licensed under the Apache 2.0 License. See the LICENSE file for details.