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

Goes well beyond the annotations by disclosing that it is cache-only, makes no AI-engine API calls, consumes no API quota, requires no auth, and has no rate limits. It also clarifies the snapshot file location and the empty-series behavior when no snapshots exist, all of which materially affect calling decisions.

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?

Front-loads purpose in the first clause, then layers behavioral and return details. Slight redundancy between 'cache-only... costs no API quota' and 'No auth required. No rate limits,' and the return-value enumeration partly overlaps the existing output schema, but overall it is dense and earns its length.

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?

Complete for a read-only reporting tool: purpose, prerequisites, cache semantics, return shape, and edge case (empty series) are all covered. With an output schema present, the added interpretation of the deltas is a bonus rather than a required element.

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 100%, so both parameters are already documented. The description adds only marginal meaning ('use since to restrict the time window'), restating what the schema says, so the baseline of 3 is appropriate.

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?

States a specific verb (report) and resource (citation rate over time), scoped clearly to 'a panel from stored snapshots'. This distinguishes it from siblings like citations_check (point-in-time) and citations_freshness, letting an agent differentiate without opening a schema.

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?

Explicitly names the prerequisite sibling ('Use panel_run to accumulate snapshots first') and explains the role of the since parameter for narrowing the window. It gives clear usage context but does not state when-not to use it versus alternatives like citations_check or panel_track.

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