get_corpus_stats

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

With no annotations, the description carries the burden. It discloses the tool's read-only nature (returning counts and values) and adds useful context like 'data freshness.' It could explicitly state 'read-only' or mention absence of side effects, but the implied safe discovery purpose is fairly transparent for a zero-parameter stats tool.

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, tightly focused, and front-loaded with the core action. The second sentence adds essential usage guidance without redundancy. Every word earns its place.

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, parameterless tool with no output schema, the description is quite complete: it lists the main output categories (counts, filter values, data freshness) and explains its role relative to other tools. It could elaborate on data structure or format, but given the minimal complexity, this is sufficient.

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 tool has zero parameters, and schema coverage is trivially 100%. Per the baseline for 0 params, the description adds no parameter-specific detail but also doesn't need to. It correctly focuses on the tool's output, which serves the discovery purpose.

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 returns counts, available filter values (tracks, regions), and data freshness for the corpus. This specific verb+resource phrasing ("Return counts...") distinguishes it from sibling search tools, making its purpose unambiguous.

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 explicitly instructs to call this tool 'first' to discover valid track and region values for other tools, providing clear when-to-use guidance. It implicitly excludes use for direct search/lookup since its role is discovery, which differentiates it from siblings.

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