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

Annotations already cover the read-only, non-destructive safety profile. The description adds real behavioral value beyond that: it explains the phase lifecycle ('done' vs 'partial'/'failed') that determines whether data is final, and what a failed/partial run yields. This is substantive lifecycle context not present in the annotations.

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 core purpose, then lifecycle semantics, then the alternative. It is somewhat dense and spends notable text enumerating return fields (prioritizedIssues, quickScan, phase, message) that an existing output schema already captures, which is mild redundancy rather than waste.

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 a 1-param read-only tool with annotations and an output schema, the description is complete: it covers purpose, phase-gated finality, partial/failed behavior, and routes to wait_for_results. Nothing needed to call it correctly is missing.

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 0% for the single testId parameter, so the schema contributes nothing and the description must compensate. It only refers to 'a test' indirectly and gives no hint about the identifier's format or source (e.g., launch_usability_test). The required param remains semantically thin.

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 and resource ('Returns the usability results for a test') and clearly distinguishes itself from get_test_status by describing what results (issues, fix prompts) are returned. It names the sibling wait_for_results, so an agent can tell the two apart without opening schemas.

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?

Gives clear context: results are final only when phase is 'done', and partial/failed runs return partial findings. It names the alternative wait_for_results for waiting until completion. No explicit exclusions ('do not use when...'), but the selection conditions are well conveyed.

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