stl_snapshot_list

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

Annotations already provide readOnlyHint, idempotentHint, and destructiveHint, covering behavioral aspects. The description does not contradict these and adds no misleading side-effect info, so the lower bar for annotation-covered cases is comfortably met.

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 content is extremely concise, with only two sentences and no fluff. Every word contributes to understanding the tool's purpose and parameters.

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?

An output schema is present, so return details need not be described. The description covers ordering (newest-first) and filtering, making it complete enough for usage. Minor ambiguity about 'pins' does not reduce usability.

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?

Although the input schema has no descriptions, the tool description text explicitly explains both parameters: kind is 'gtfs' or 'rt', and source is a name like 'metro_gtfs'. This adds meaning beyond the bare types and defaults in the 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 lists stored snapshots newest-first with pins, using specific verbs and a distinct resource. This differentiates it from siblings like stl_snapshot_sources, which likely lists sources, and stl_snapshot_fetch, which likely fetches a snapshot.

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?

The description explains how to filter using kind and source, including examples and the instruction to omit for all. It does not explicitly compare with alternatives, but the usage pattern is straightforward and well-implied.

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