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

Beyond the annotations (readOnlyHint=true, destructiveHint=false), the description adds rich behavioral context: newest-first ordering, the funnel stages ('scanned → dropped by fit → dropped by intent → added / duplicates / capped'), inclusion of ICP facets LinkedIn could not filter on, and provider refusal status/message. It also helps interpret the results, which is more than annotations alone provide.

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 three sentences, front-loaded with the core return content, followed by the practical diagnostic use case, and closes with the safety note 'Read-only.' No word is wasted; every sentence 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?

There is no output schema, so the description itself must convey return semantics. It explains the funnel stages, the facets, and provider refusal info, plus the interpretation guidance. For a read-only diagnostic tool with three well-documented parameters, this is 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 input schema already has 100% description coverage, with detailed explanations for playId, key, and limit. The tool description adds no further parameter-level semantics—it focuses on the output. Per the rubric, baseline 3 is appropriate when the schema carries the full burden.

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 resource ('run history of ONE lane') with precise content (funnel stages, ICP facets, provider refusal status). It also contrasts with sibling tools by framing the diagnostic purpose ('tell 'the query returns nobody' from 'everyone was already a lead' from 'LinkedIn is rate-limiting the seat''). It is easily distinguishable from nearby tools like gtm_play_stats or gtm_show_play.

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 gives an explicit when-to-use with the three-way diagnostic phrase. It does not name alternative tools or provide when-not-to-use guidance, so it falls just short of the 5-level 'explicit when/when-not/alternatives' standard. The context is nevertheless clear and actionable.

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