bart_departuresGet real-time departures from a BART station.
Args:
station: 4-letter abbreviation (e.g. EMBR, 24TH)
direction: Optional 'n' or 's'
| Name | Required | Description | Default |
|---|---|---|---|
| station | Yes | Station code (e.g. EMBR, 24TH) | |
| direction | No | Direction filter |
| Name | Required | Description | Default |
|---|---|---|---|
| departures | Yes |
Changes observed during successful MCP inspections. Dates show when Glama detected each change.
Output schema / (root)Previous value: -nullNew value: +{
+ "$schema": "http://json-schema.org/draft-07/schema#",
+ "additionalProperties": false,
+ "properties": {
+ "departures": {
+ "items": {
+ "additionalProperties": false,
+ "properties": {
+ "bikeFlag": {
+ "type": [
+ "string",
+ "null"
+ ]
+ },
+ "color": {
+ "type": [
+ "string",
+ "null"
+ ]
+ },
+ "destination": {
+ "type": [
+ "string",
+ "null"
+ ]
+ },
+ "direction": {
+ "type": [
+ "string",
+ "null"
+ ]
+ },
+ "displayMinutes": {
+ "type": "string"
+ },
+ "hexColor": {
+ "type": [
+ "string",
+ "null"
+ ]
+ },
+ "length": {
+ "type": [
+ "number",
+ "null"
+ ]
+ },
+ "minutes": {
+ "type": [
+ "number",
+ "null"
+ ]
+ },
+ "platform": {
+ "type": [
+ "string",
+ "null"
+ ]
+ },
+ "station": {
+ "type": "string"
+ },
+ "stationCode": {
+ "type": "string"
+ }
+ },
+ "required": [
+ "station",
+ "stationCode",
+ "destination",
+ "minutes",
+ "displayMinutes",
+ "direction",
+ "platform",
+ "length",
+ "color",
+ "hexColor",
+ "bikeFlag"
+ ],
+ "type": "object"
+ },
+ "type": "array"
+ }
+ },
+ "required": [
+ "departures"
+ ],
+ "type": "object"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already indicate readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds the station abbreviation format and optional direction, but does not disclose additional behaviors like rate limits, data source, or output details. No contradiction with annotations.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is exceptionally concise, with a clear purpose statement followed by a compact arg list. It is front-loaded and free of unnecessary prose. The arg list is slightly redundant with the schema, but this does not detract from overall clarity.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a simple read-only tool with good annotations and output schema, the description is largely sufficient. It covers the core purpose and essential parameter syntax. However, it lacks context on direction semantics (e.g., which directions correspond to n/s) and when to prefer this over sibling tools, leaving minor gaps.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 100% (both parameters have descriptions). The description's arg list mostly repeats schema information, adding '4-letter abbreviation' and 'Optional,' which are already implied by schema constraints (minLength, required, enum). Minimal added value beyond schema.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states the tool's function with a specific verb and resource: 'Get real-time departures from a BART station.' This distinguishes it from sibling tools like bart_advisories, bart_fare, and bart_trip, which serve different purposes.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
No guidance is provided on when to use this tool versus alternatives. It does not mention exclusions, prerequisites, or appropriate scenarios, beyond implying the need for a station abbreviation.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Most tools have clearly distinct purposes, but bart_advisories and bart_status_summary both relate to service status, and bart_trip includes fare information alongside bart_fare. Descriptions help clarify the intended use of each, so the overlap is minor.
All tools consistently use the 'bart_' prefix followed by a descriptive noun phrase in snake_case (e.g., bart_stations, bart_fare, bart_trip). This creates a predictable and uniform naming pattern.
Seven tools is well-scoped for a transit information server, covering station lookup, departures, advisories, fares, and trip planning without unnecessary redundancy or bloat.
The tool set comprehensively covers the core BART transit needs: station discovery, real-time departures, trip planning, fare calculation, and service advisories. No obvious gaps exist for typical transit-related queries.