Skip to main content
Glama

List Transit Service Alerts

transit_list_service_alerts
Read-onlyIdempotent

Check live service alerts for Bay Area transit delays, outages, detours, and planned disruptions. Filter by agency or keyword to see what's affecting your commute.

Instructions

Service alerts — delays, outages, detours and planned disruptions.

Answers "is BART running normally", "why is my line delayed" and "anything I should know before I leave". Omit operator_id to sweep every Bay Area agency in a single request, which is also the kinder option against the hourly quota.

Args:

  • operator_id (string): limit to one agency; omit for all operators

  • query (string): substring match on the headline or description

  • active_only (boolean): only alerts whose active period covers now (default: true)

  • limit (number): maximum alerts to return (default: 25)

  • response_format ('markdown' | 'json'): output format (default: 'markdown')

Returns: { "count": number, "total": number, "truncated": boolean, "alerts": [ { "id": string, "header": string, "description": string, "effect": string, "cause": string, "routes": [string], "start": number, "end": number } ] // epoch SECONDS }

Examples:

  • "Any BART delays?" -> operator_id='BA'

  • "Anything wrong on my commute?" -> omit operator_id, read across agencies

  • "Weekend track work?" -> active_only=false, query='weekend'

  • Don't use when: you want a specific stop's arrivals (use transit_next_departures)

Error Handling:

  • No alerts is genuinely good news, not an error — it means normal service

  • Timestamps here are epoch seconds, unlike the ISO strings elsewhere in this API

  • Setting active_only=false surfaces future planned work as well as current problems

  • 511 allows 60 requests per hour across ALL endpoints

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
limitNoMaximum results to return (max 200)
queryNoCase-insensitive substring match on the alert headline or description
active_onlyNoOnly alerts whose active period covers now
operator_idNoLimit to one agency; omit for alerts across every Bay Area operator
response_formatNoOutput format: 'markdown' for human-readable, 'json' for machine-readablemarkdown

Output Schema

TableJSON Schema
NameRequiredDescriptionDefault
countYes
totalYes
alertsYes
truncatedYes
Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations only indicate read-only, idempotent, and non-destructive behavior. The description adds crucial behavioral nuance: no alerts means normal service (not an error), timestamps are epoch seconds unlike the ISO strings in other API endpoints, active_only=false surfaces future planned work, and rate limits. This goes well beyond the annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Structured with Args, Returns, Examples, and Error Handling sections. The purpose and primary use cases are front-loaded in the first sentence, and every sentence adds value—examples, rate limits, or format distinctions. No redundancy or fluff.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The output schema is present and the description includes a return format example with field types. It covers error handling (no alerts ≠ error), rate limits, timestamp format, and sibling routing. For a 5-parameter tool with no required parameters, this is fully complete for an agent.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters5/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the baseline is 3, but the description adds substantial meaning: operator_id omission sweeps all agencies and is 'kinder' against quota, active_only=false is tied to 'weekend track work' examples, and query is illustrated with a practical use case. These contextual insights help an agent choose parameter values effectively.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific verb ('List') and resource ('Transit Service Alerts'), and grounds it with concrete questions it answers ('is BART running normally', 'why is my line delayed'). It explicitly differentiates from the sibling transit_next_departures by naming when not to use it, making the purpose unmistakable.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly states when to use the tool (answering delay/outage questions) and when not to ('Don't use when: you want a specific stop's arrivals (use transit_next_departures)'). Also gives operational guidance, such as omitting operator_id to sweep all agencies and conserve quota—practical context an agent needs.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Install Server

Other Tools

Latest Blog Posts

MCP directory API

We provide all the information about MCP servers via our MCP API.

curl -X GET 'https://glama.ai/api/mcp/v1/servers/RyK57/transit-mcp-server'

If you have feedback or need assistance with the MCP directory API, please join our Discord server