# io.github.cyanheads/openaq-mcp-server (remote · openaq.caseyjhand.com)

Find air-quality stations and read pollutant observations from government monitors via OpenAQ v3.

- Trust score: 71/100 (medium)
- Change this week: +4
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-08-04

## Components

- remote · `openaq.caseyjhand.com`: 71/100 (this document), [markdown](https://verifymcp.io/servers/cyanheads-openaq-mcp-server/openaq.md), [page](https://verifymcp.io/servers/cyanheads-openaq-mcp-server/openaq)
- npm · `@cyanheads/openaq-mcp-server`: 35/100, [markdown](https://verifymcp.io/servers/cyanheads-openaq-mcp-server/cyanheads-openaq-mcp-server.md), [page](https://verifymcp.io/servers/cyanheads-openaq-mcp-server/cyanheads-openaq-mcp-server)

## Channel facts

- Endpoint: `https://openaq.caseyjhand.com/mcp`
- Transports: `streamable-http`
- Auth: `none`
- Version: `0.1.7`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. Scores are 0–100 per category. Scoring method: https://verifymcp.io/docs/scoring (what has changed: https://verifymcp.io/docs/scoring/changelog)

Scored 2026-08-04.

- **Endpoint Security**: 66/100
  - The endpoint's TLS certificate is valid, in date, and uses a strong key.
  - Authorisation not fully verified: no authorisation is required to call this server, and 7 tool(s) never declared a destructiveHint. The MCP spec treats an absent hint as destructive by default, so we cannot call this surface safe.
  - HTTPS is enforced; there's no plaintext access path.
  - The HSTS (Strict-Transport-Security) header is present.
  - DNSSEC is configured correctly; the domain's records validate against the full chain to the root.
- **Transport & Reachability**: 100/100
  - Verified streamable-http transport via a live MCP handshake.
- **Schema Quality & AI Usability**: 77/100
  - 100% of prompts and resources have a non-trivial description (not blank, and not just the item's name).
  - AI-judged instruction clarity (excellent).
  - Context-footprint check failed: tool/resource definitions use about 2312 tokens (~289/item across 8 items; 7 tools + 1 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 30/100
  - Stability observed for 9 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 100/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 100% of tool parameters carry a description.
  - Structured output schemas are declared (100% of tools); any adoption earns full credit.
- **Capabilities**: 100/100
  - Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.

## Install

### Claude

```bash
claude mcp add --transport http cyanheads-openaq-mcp-server https://openaq.caseyjhand.com/mcp
```

### Codex

```toml
[mcp_servers.cyanheads-openaq-mcp-server]
url = "https://openaq.caseyjhand.com/mcp"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "cyanheads-openaq-mcp-server": {
      "type": "remote",
      "url": "https://openaq.caseyjhand.com/mcp",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add cyanheads-openaq-mcp-server --url https://openaq.caseyjhand.com/mcp --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  cyanheads-openaq-mcp-server:
    url: "https://openaq.caseyjhand.com/mcp"
```

### Other

```json
{
  "mcpServers": {
    "cyanheads-openaq-mcp-server": {
      "type": "http",
      "url": "https://openaq.caseyjhand.com/mcp"
    }
  }
}
```

The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.

## Changelog

Every change recorded for this component, newest first. Days that predate change tracking, or that we cannot explain, say so: "we were watching and nothing happened" and "we were not watching" are different claims.

### 2026-08-03 (score 71, +1)

No change was recorded against any check on this day. Stability & Change Management went from 23 to 27. That category is still filling its 30-day observation window: 7 days of observed history at the previous scan, 8 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-08-01 (score 70, +1)

No change was recorded against any check on this day. Stability & Change Management went from 17 to 20. That category is still filling its 30-day observation window: 5 days of observed history at the previous scan, 6 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-07-31 (score 69, +1)

- [functional] We updated how we score, so this day's move reflects our rubric, not a change to the server

### 2026-07-30 (score 68, +1)

- [functional] We updated how we score, so this day's move reflects our rubric, not a change to the server

### 2026-07-28 (score 67, +1)

No change was recorded against any check on this day. Stability & Change Management went from 3 to 7. That category is still filling its 30-day observation window: 1 days of observed history at the previous scan, 2 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-07-27 (score 66, 0)

- [functional] We updated how we score, so this day's move reflects our rubric, not a change to the server

### 2026-07-26 (score 66)

First indexed and scored.

## MCP tools (7)

### `openaq_find_locations` (~551 tokens)

openaq-mcp-server: find locations

Find air-quality monitoring stations (measured by physical sensors, not modeled) near a point, within a bounding box, or by country. Returns each station's id, name, coordinates, distance from the query point (when searching by coordinates), country, provider, the parameters its sensors measure, and the timestamp of its most recent data (datetimeLast). Required first step: openaq_get_readings and openaq_get_measurements key on the location id this returns. Coverage is uneven and real — a station only reports the parameters it measures, and the absence of a nearby station means no monitoring there, not clean air. For dense modeled coverage anywhere on Earth, use open-meteo-mcp-server's air-quality tool instead.

Input parameters:

- `bbox` (string): Bounding box as "minLon,minLat,maxLon,maxLat" (west,south,east,north). Alternative to coordinates+radius for area sweeps. Results have no distance field (no center point).
- `coordinates` (string): Center point as "latitude,longitude" (e.g. "47.6062,-122.3321"). Pair with radius for a near-me search. Resolve a place name to coordinates with openstreetmap-mcp-server or open-meteo geocode first.…
- `iso` (string): Restrict to a country by ISO 3166-1 alpha-2 code (e.g. "US", "IN", "DE"). Combine with bbox/coordinates to scope, or use alone for a country-wide list. Discover coverage with openaq_list_countries.
- `limit` (integer): Max stations to return (1–100). Default 20. Results are ordered by distance when searching by coordinates.
- `page` (integer): Which page of results to return (1-based). Default 1. The only way past the 100-station cap: with limit 100, page 2 returns stations 101–200. Distance ordering applies within a page, not across pages…
- `parametersId` (integer): Only return stations that measure this parameter id (e.g. 2 = PM2.5 µg/m³). Get ids from openaq_list_parameters — the same pollutant has several ids for different units. Narrows the station set; each…
- `radius` (integer): Search radius in metres around coordinates (1–25000; the API hard-caps at 25000). Default 12000 (~12km). Only used with coordinates.

Output parameters:

- `cap` (number): The limit that was applied.
- `locations` (array): Matching stations. Empty array means no monitoring coverage for the query — NOT clean air. Widen the radius, try openaq_list_countries, or use the modeled open-meteo air-quality tool.
- `notice` (string): Guidance when OpenAQ reports a lower-bound total without the result set hitting the limit.
- `shown` (number): Number of stations returned.
- `totalCount` (number): Total matching stations before the limit. A floor (not an exact count) when totalCountIsLowerBound is true.
- `totalCountIsLowerBound` (boolean): True when OpenAQ reported a lower bound (">N"): totalCount is a floor and more stations match than the count shown.
- `truncated` (boolean): True when the station list was capped at the limit.

### `openaq_get_readings` (~272 tokens)

openaq-mcp-server: get readings

Latest measured value for every sensor at a monitoring station — the current-conditions tool. Returns one record per parameter, each with the value, its unit, the UTC and local timestamp, and the sensor id, joined so every value carries its pollutant and unit (the raw latest feed is keyed only by sensor id). Pass a locationId from openaq_find_locations, or pass coordinates to auto-resolve to the nearest station that measures the requested parametersId. Data recency varies by station reporting cadence — read each value's timestamp to know whether "latest" is minutes or hours old. These are measured observations with coverage gaps, not a modeled grid.

Input parameters:

- `coordinates` (string): Fallback "latitude,longitude" when you do not have a locationId — resolves to the nearest station (within 25km) that measures parametersId, then reads its latest values. Requires parametersId.
- `locationId` (integer): Station id from openaq_find_locations. Provide this OR coordinates. When set, returns the latest value for every sensor at this station.
- `parametersId` (integer): Required with coordinates: which parameter id the nearest station must measure (get ids from openaq_list_parameters). With locationId, optionally filters the returned values to this parameter id; omi…

Output parameters:

- `location` (object): The station these readings came from
- `notice` (string): Guidance when the station resolved but returned no recent values.
- `readings` (array): Latest value per sensor. An old datetime means the station reports infrequently or is stale — not that the value is current.

### `openaq_get_measurements` (~527 tokens)

openaq-mcp-server: get measurements

Historical measurement series for one pollutant at one station over a date range — for trend analysis and "was last week worse than the monthly average?". Pass a locationId and a parametersId and work in stations — you get the series for that pollutant at that station. Choose aggregation: raw (every reported value), hourly, or daily — daily and hourly add a per-bucket statistical summary (min, median, max, mean, sd). Large ranges produce thousands of rows and spill to a DataCanvas: the response returns a preview plus a canvasId and table name you query with openaq_dataframe_query. Values carry their unit; the server never converts between µg/m³, ppm, and ppb.

Input parameters:

- `aggregation` (string): Time bucketing. "raw" = every reported value (often hourly at source). "hourly"/"daily" = server-side rollups with a statistical summary per bucket. Use "daily" for multi-month trends to keep the ser…
- `canvas_id` (string): DataCanvas id from a prior call to reuse the same canvas (e.g. to compare two stations' series side by side). Omit to start fresh; the response returns a new canvas_id when the series spills.
- `datetimeFrom` (string): Start of the range, inclusive. Date "YYYY-MM-DD" (opens at 00:00:00Z that day) or full UTC "YYYY-MM-DDTHH:MM:SSZ". Omit to get the most recent values.
- `datetimeTo` (string): End of the range, inclusive. Date "YYYY-MM-DD" covers that whole day (closes at 23:59:59Z) or full UTC "YYYY-MM-DDTHH:MM:SSZ". Must land after datetimeFrom — the two forms mix freely, so "2026-06-25"…
- `limit` (integer): Max rows per page from the API (1–1000). Default 1000. The tool pages internally up to the spill threshold.
- `locationId` (integer, required): Station id from openaq_find_locations.
- `parametersId` (integer, required): Parameter id to pull the series for (e.g. 2 = PM2.5 µg/m³). Get ids from openaq_list_parameters. Must be a parameter the station measures — find_locations lists each station's parameters.

Output parameters:

- `aggregation` (string): Bucketing applied
- `canvasId` (string): DataCanvas id holding the pulled series. Query with openaq_dataframe_query. The pull stops at 5000 rows, so this is the whole series only when totalCount is at or below that — read the notice, which…
- `location` (object): Station the series came from
- `notice` (string): What limited this response, when something did — the row cap, a failed page, or DataCanvas being unavailable — plus how to reach the rest.
- `parameter` (object): What was measured, resolved from the station's sensor
- `rowCount` (number): Rows in this response (preview length when spilled)
- `sensorId` (number): Resolved sensor id the series was pulled from
- `series` (array): The (possibly previewed) series, newest or oldest first per the API. When truncated, this is a preview — query canvasId for the rows staged there.
- `tableName` (string): Canvas table name for the staged series (e.g. "measurements_1701"). Reference it in SQL.
- `totalCount` (number): Total rows in the full series.
- `truncated` (boolean): True when the series exceeded the inline limit, so series is a preview and the pulled rows were staged on canvasId. Absent/false when everything fit inline. It says nothing about whether the pull its…

### `openaq_list_parameters` (~241 tokens)

openaq-mcp-server: list parameters

Catalog of every measurable pollutant and its canonical unit: id, code, display name, unit, and a one-line description (pm25, pm10, o3, no2, so2, co, bc, and ~38 more). This is the unit-disambiguation reference — the same pollutant exists under several ids with different units (CO is id 4 in µg/m³, id 8 in ppm, id 102 in ppb), so use this to pick the exact parametersId for openaq_find_locations / openaq_get_readings / openaq_get_measurements and to interpret a reading's unit. A small bounded catalog fetched live from OpenAQ.

Input parameters:

- `pollutantsOnly` (boolean): When true, exclude meteorological/auxiliary parameters (temperature, humidity, wind, pressure, particle-count channels) and return only air pollutants. Default false (full catalog).
- `query` (string): Case-insensitive filter over the bounded parameter catalog (~44) by code, display name, and description (e.g. "pm" for particulates, "ozone", "co"). Omit to list everything.

Output parameters:

- `notice` (string): Guidance when the query matched nothing.
- `parameters` (array): Matching parameters. Multiple rows can share a name with different ids/units — pick the id whose unit you want.
- `totalCount` (number): Total parameters matched after filtering.

### `openaq_list_countries` (~241 tokens)

openaq-mcp-server: list countries

Catalog of country-level coverage: id, ISO code, name, the date span of available station data (datetimeFirst/datetimeLast), and which parameters are measured anywhere in that country. The availability check before a regional sweep — answers "which countries have NO2 monitoring?" and tells you whether a country has recent data before you call openaq_find_locations. Coverage is uneven worldwide; this surfaces where measured data exists.

Input parameters:

- `parametersId` (integer): Only return countries that measure this parameter id somewhere (e.g. 2 = PM2.5 µg/m³) — the one-call answer to "which countries have NO2 monitoring?". Get ids from openaq_list_parameters; the same po…
- `query` (string): Case-insensitive filter over the bounded country catalog (~153) by code and name. A two-letter query is treated as an exact ISO 3166-1 alpha-2 code (e.g. "US" → United States); longer queries match a…

Output parameters:

- `countries` (array): Matching countries with coverage metadata.
- `notice` (string): Guidance when the query matched nothing.
- `totalCount` (number): Total countries matched after filtering.

### `openaq_dataframe_query` (~153 tokens)

openaq-mcp-server: dataframe query

Run a read-only SQL SELECT against the measurement tables openaq_get_measurements staged on a DataCanvas. Reference tables by the name the measurements call returned (measurements_<sensorId>). For aggregation (monthly means, exceedance counts) and cross-sensor comparison over series too large to inline. Only SELECT is allowed — writes, DDL, and file/network table functions are rejected.

Input parameters:

- `canvas_id` (string, required): DataCanvas id returned by openaq_get_measurements when a series spilled.
- `sql` (string, required): Read-only SELECT. Reference tables by the names openaq_get_measurements returned (e.g. measurements_1701). Use openaq_dataframe_describe first to see table and column names.

Output parameters:

- `rowCount` (number): Full result count before the row cap.
- `rows` (array): Result rows (capped at the canvas row limit).

### `openaq_dataframe_describe` (~85 tokens)

openaq-mcp-server: dataframe describe

List the tables and columns staged on a DataCanvas so you can write valid SQL for openaq_dataframe_query without guessing column names. Returns each measurement table (measurements_<sensorId>) with its row count and column names. Requires DataCanvas to be enabled.

Input parameters:

- `canvas_id` (string, required): DataCanvas id returned by openaq_get_measurements when a series spilled.

Output parameters:

- `notice` (string): Guidance when the canvas holds no tables yet.
- `tables` (array): Tables currently staged on the canvas.

## Diagnostics

Captured diagnostic sections: TLS, DNSSEC, Authorisation, Transports. The full working is on the page: https://verifymcp.io/servers/cyanheads-openaq-mcp-server/openaq#diagnostics

## Score history

- 2026-08-04: 71
- 2026-08-03: 71
- 2026-08-02: 70
- 2026-08-01: 70
- 2026-07-31: 69
- 2026-07-30: 68
- 2026-07-28: 67
- 2026-07-27: 66
- 2026-07-26: 66

## Links

- Remote endpoint: https://openaq.caseyjhand.com/mcp
- Repository: https://github.com/cyanheads/openaq-mcp-server
- Changelog RSS feed: https://verifymcp.io/servers/cyanheads-openaq-mcp-server/openaq/changelog.xml
- Changelog JSON feed: https://verifymcp.io/servers/cyanheads-openaq-mcp-server/openaq/changelog.json
- HTML version of this page: https://verifymcp.io/servers/cyanheads-openaq-mcp-server/openaq