prt_get_vehiclesFetch live Pittsburgh Regional Transit vehicle data, filtering by route, vehicle ID, or data feed to enable real-time transit tracking.
Fetch live vehicle data via getvehicles.
| Name | Required | Description | Default |
|---|---|---|---|
| rt | No | Optional route filter | |
| vid | No | Optional vehicle id filter | |
| rtpidatafeed | No |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, openWorldHint, and idempotentHint, so the safety and side-effect profile is covered. The description adds only that the data is "live," which is a small but real piece of context; it says nothing about rate limits, refresh cadence, or return volume.
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?
A single short sentence, front-loaded with the core action, with no wasted preamble. The trailing "via getvehicles" is redundant with the tool name and marginally costs it a point.
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 three-parameter tool with an undocumented parameter, no output schema, and no annotation-independent behavior notes, the description is far too thin. It does not tell the agent what the live feed returns or how filtering params interact.
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 description coverage is 67%: rt and vid are documented as optional filters, but rtpidatafeed has no description anywhere. The description adds no parameter meaning at all, so it fails to compensate for the uncovered parameter.
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?
States a verb and resource ("Fetch live vehicle data"), and the resource name does loosely distinguish it from siblings like get_routes or get_predictions. However, it leans on the tool name and appends a redundant API endpoint reference ("via getvehicles") instead of clarifying scope, so it is vague rather than specific.
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 on when to use this versus the six sibling prt_get_* tools, no mention of prerequisites, filters, or common workflows. The agent must infer that this is the vehicle-position endpoint purely from the name.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.