Perch builtin packages

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

No annotations are provided, so the description carries the full behavioral burden. It clearly states the two modes: without id, list packages; with id, return all files of that package. This is transparent about the core read-only behavior. It doesn't mention edge cases like invalid ids or output format, but it covers the primary behavior sufficiently.

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 two sentences with no fluff. It front-loads the purpose and concisely captures the conditional branching behavior. Every word earns its place, making it highly efficient.

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 one-parameter tool with no output schema or annotations, the description covers the essential behavior. The only gap is the lack of detail on what 'returns every file' means (e.g., file paths, contents, or metadata) and how invalid ids are handled. These are minor for a tool this simple, so it is nearly complete.

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?

The schema has zero description coverage for the only parameter `id`. The description fully compensates by explaining that absent `id` triggers a list operation, while present `id` returns the files of that package. This adds concrete semantic meaning beyond the raw string type 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's function: 'lists' builtin packages without an id and 'returns every file of that package' with an id. It identifies the resource (Perch packages) and the conditional behavior, distinguishing it from sibling tools like perch_guide or perch_docs by framing these as 'complete worked examples of the vocabulary.'

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 implies usage: use it to see the builtin examples, with or without an id. However, it does not explicitly contrast with sibling tools (e.g., when to use perch_examples vs perch_docs or perch_vocabulary), nor does it state any prerequisites or exclusions. Usage context is clear but not fully articulated.

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