prt_get_predictionsFetch real-time arrival predictions for PRT transit stops by stop ID. Provide comma-separated stop IDs to get upcoming arrival times.
Fetch arrival predictions for one or more stop IDs.
| Name | Required | Description | Default |
|---|---|---|---|
| top | No | Maximum predictions to return | |
| stpid | Yes | Stop ID(s), comma-separated | |
| 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, covering the basic safety profile. The description adds no further behavioral context such as rate limits, real-time data freshness, or return format.
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 a single front-loaded sentence with no redundant or wasted words. It is appropriately sized for a concise statement of purpose.
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 prediction tool with no output schema, the description omits the return format, data freshness, and the purpose of the undocumented rtpidatafeed parameter. While annotations cover safety, the definition leaves significant gaps for an agent to fully leverage the tool.
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% (2 of 3 parameters documented), so the baseline is 3. The description's mention of 'one or more stop IDs' mirrors the schema's own description for stpid and adds no new semantic detail, while rtpidatafeed remains undocumented.
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 states a specific verb ('Fetch') and resource ('arrival predictions') scoped to 'stop IDs,' making the tool's purpose clear. It does not explicitly differentiate itself from the six sibling tools, so it falls short of a 5.
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?
There is no guidance on when to use this tool versus alternatives, nor any exclusions or prerequisites. The phrase 'for one or more stop IDs' provides minimal context but does not constitute usage guidelines.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.