# mbta.transit.alerts

Get active Boston MBTA service disruption alerts — delays, cancellations, detours, shuttle buses, station closures, and elevator/escalator outages. Returns alert header, effect type, cause, severity (0–10), lifecycle status, affected routes and stops, and active time period. Filter by route ID (e.g. "Red"), stop ID, minimum severity, lifecycle (ONGOING/UPCOMING/NEW), or effect type (DELAY/CANCELLATION/SHUTTLE/DETOUR/SUSPENSION). Severity 7+ = moderate disruption; 9–10 = major service change. MassDOT Open Data License, real-time data, no upstream cost.

Agent View of the PolicyLayer registry record for `mbta.transit.alerts`. HTML page: https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/mbta.transit.alerts

## Facts

- Tool: `mbta.transit.alerts`
- Server: Apibase (`apibase-mcp-client`) — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase.md
- Install: `npx -y apibase-mcp-client`
- Homepage: https://github.com/whiteknightonhorse/APIbase
- Risk category: Read (Low risk)
- Registry record: grade F, identity unverified
- Server auth posture: open
- Server rate-limited: no
- Parameters: 6
- Recommended policy verdict: Allowed

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `stop` | string | no | Filter alerts by stop ID (e.g. "place-sstat" for South Station). Use mbta-transit.stops to get IDs. |
| `limit` | integer | no | Maximum number of alerts to return (default 20, max 50) |
| `route` | string | no | Filter alerts by route ID (e.g. "Red", "Green-B", "1", "CR-Providence"). Use mbta-transit.routes to get IDs. |
| `effect` | string | no | Filter by disruption effect type: "DELAY", "CANCELLATION", "SUSPENSION", "SHUTTLE", "DETOUR", "STATION_CLOSURE", etc. |
| `severity` | integer | no | Minimum severity level 0–10: 0–3=informational, 4–6=minor disruption, 7–8=moderate, 9–10=major/shutdown. Omit for all. |
| `lifecycle` | string | no | Filter by alert lifecycle: "ONGOING" (active now), "UPCOMING" (future planned), "NEW" (just created) |

Parameters from the server's own tool schema.

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "mbta.transit.alerts",
    "arguments": {}
  }
}
```

## Why mbta.transit.alerts is rated Low

Retrieves real-time transit alert data with no side effects or data modification capabilities.

From the tool's own definition: "Get active Boston MBTA service disruption alerts; returns alert header, effect type, cause, severity."

## Use case

AI agents call mbta.transit.alerts to retrieve information from Apibase without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

## Recommended policy (PolicyLayer)

Verdict: **Allowed**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Apibase:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "mbta.transit.alerts": {}
  }
}
```

## Other tools on Apibase (1383)

- `infra.cloudflare.dns_delete` — Destructive — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/infra.cloudflare.dns-delete.md
- `infra.cloudflare.purge_cache` — Destructive — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/infra.cloudflare.purge-cache.md
- `polymarket.trading.cancel_order` — Destructive — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/polymarket.trading.cancel-order.md
- `ai.image.generate` — Execute — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/ai.image.generate.md
- `aipush.market.report` — Execute — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/aipush.market.report.md
- `audio.transcribe.submit` — Execute — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/audio.transcribe.submit.md
- `dev.code.execute` — Execute — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/dev.code.execute.md
- `device.registry.command` — Execute — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/device.registry.command.md
- `document.convert.from_pdf` — Execute — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/document.convert.from-pdf.md
- `document.convert.to_pdf` — Execute — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/document.convert.to-pdf.md
- `document.convert.web_to_pdf` — Execute — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/document.convert.web-to-pdf.md
- `hf_inference.nlp.translate` — Execute — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/hf-inference.nlp.translate.md
- `infra.browser.create_session` — Execute — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/infra.browser.create-session.md
- `phone.telnyx.sms_world` — Execute — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/phone.telnyx.sms-world.md
- `phone.twilio.sms` — Execute — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/phone.twilio.sms.md
- `platform.batch.call` — Execute — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/platform.batch.call.md
- `scb.tables.query` — Execute — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/scb.tables.query.md
- `socrata.datasets.query` — Execute — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/socrata.datasets.query.md
- `web.screenshot.capture` — Execute — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/web.screenshot.capture.md
- `domain.namesilo.register` — Financial — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/domain.namesilo.register.md
- `phone.telnyx.sms_premium` — Financial — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/phone.telnyx.sms-premium.md
- `polymarket.trading.place_order` — Financial — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/polymarket.trading.place-order.md
- `abr.business.abn_lookup` — Read — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/abr.business.abn-lookup.md
- `abr.business.acn_lookup` — Read — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/abr.business.acn-lookup.md
- `abr.business.name_search` — Read — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/abr.business.name-search.md
- `abs.demographics.population` — Read — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/abs.demographics.population.md
- `abs.economy.cpi` — Read — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/abs.economy.cpi.md
- `abs.economy.gdp` — Read — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/abs.economy.gdp.md
- `abs.economy.labour_force` — Read — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/abs.economy.labour-force.md
- `abs.economy.trade` — Read — https://policylayer.com/tools/io-github-whiteknightonhorse-apibase/abs.economy.trade.md
- …and 1353 more: https://policylayer.com/tools/io-github-whiteknightonhorse-apibase.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=io-github-whiteknightonhorse-apibase · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/io-github-whiteknightonhorse-apibase