check_staleness_tool

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

With no annotations provided, the description carries the full burden. It explicitly states that the tool is read-only and discloses the UNCHECKABLE return condition for missing recorded facts. It also clarifies that it does not perform fuzzy searching. This provides meaningful behavioral context, though it does not detail all possible outputs or error conditions, which are partly covered by the output schema.

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 exceptionally concise—three sentences. It front-loads the core purpose in the first sentence, then adds essential constraints and return behavior. No wasted words; every sentence contributes meaningful information.

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?

Given the tool has an output schema (though not shown) and no annotations, the description covers the essential aspects: purpose, read-only nature, required paths, and a special return condition. It does not explicitly discuss error handling for missing files or permissions, but the read-only designation and simple scope make this acceptable. It is largely complete for a staleness-check 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?

The schema has 0% description coverage, so the tool description must compensate. It does add value by explaining that both paths (document and source) are required and that recorded_facts affect the UNCHECKABLE return. However, it does not elaborate on the role of each parameter beyond their names (e.g., what a 'source file' is versus 'document'), leaving some semantics to be inferred.

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 action (check) and a clear subject (whether a document's figures still match a source file). It also distinguishes itself by noting that it does not search for a plausible match, which helps differentiate it from sibling tools like check_coverage_tool. The purpose is 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 implies when to use the tool (when you need to verify staleness against a named source) and provides a key constraint (both paths are required). However, it does not explicitly mention alternative tools or when not to use it, leaving some ambiguity against siblings. The guidance is implicit rather than direct.

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