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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), yet the description adds substantive behavioral context: checks are case-insensitive literal comparisons, they do not judge meaning or verify backend actions, test content is not stored or executed, and request metadata is logged. These are exactly the traits an agent needs and that annotations cannot convey.

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?

Three short sentences, front-loaded with the action and output, followed by the two most important behavioral caveats. No sentence is filler.

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?

For a one-parameter, fully-documented tool with no output schema, the description explains the produced artifact, the validation semantics, and the data-handling posture. Nothing an agent needs to invoke 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 100% for the single parameter, so the schema already documents the 1-20 test array, field names, and constraints. The description's mention of case-insensitive comparison largely restates the schema's check-field description and adds no new syntax or format detail. 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?

States a specific verb (validate) and resource (response tests), names the consuming system (PromptBrake CI), and describes the produced artifact (tests.json). An agent can distinguish this from all three siblings, which address payloads, OWASP mapping, and release planning rather than test authoring.

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 the context of use ('for PromptBrake CI') and the valid cardinality (1-20 tests), but never states when to prefer this tool over alternatives or any prerequisites for invoking it. Guidance is implied rather than explicit.

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