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

Annotations already declare readOnly, idempotent, non-destructive, open-world, so safety is covered. The description adds real behavioral context beyond that: the API-key requirement and the shape of the returned measurement data (podcast/speaker counts, bar in force, last-verified timestamp), which tells the agent what it will actually receive.

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-loaded with the resource and its contents, followed by the prerequisite, auth requirement, and a concrete example call. Dense but every clause carries information; only the example is arguably optional.

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?

With no output schema, the description carries the burden of explaining the return value and does so concretely (claim, evidence, nuance/gaps, related entries/books, measurement). Auth, slug sourcing, and an example call are all present, so an agent has everything needed to invoke it correctly.

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%, and the schema already documents both slug and _apiKey (format cc_live_..., refusal without it). The description's mention of _apiKey and slug provenance restates schema content rather than adding syntax or format guidance, so baseline 3 applies.

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?

Names a specific verb (get) and resource (CanonCannon entry for one idea) and enumerates exactly what the entry contains: claim, evidence, nuance/gaps, related entries and books, plus measurement fields. It is clearly distinguishable from canon_search, which is presented as the slug-discovery sibling rather than a duplicate.

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?

"Get the slug from canon_search" states the prerequisite and implicitly routes the agent to the search tool first. There is no explicit when-not condition, but the workflow dependency is unambiguous.

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