Decide whether failed tests should block the build

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

Annotations already declare readOnlyHint and idempotentHint, so the safety profile is covered. The description adds the key behavioral detail: the verdict and per-failure decision logic. It does not contradict annotations and provides meaningful context beyond them, though it does not detail the exact response format (already covered by output schema).

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 a single, well-structured sentence that front-loads the primary action and then explains the decision logic and return value. There is zero fluff; every clause contributes meaning.

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?

The tool is simple (two optional params, both well-documented) and the output schema exists, so the description does not need to explain return values in detail. It fully covers the core logic and provides enough context for correct invocation. No critical information 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 coverage is 100%, so both parameters are already well-described in the schema. The description adds a concrete example ('target/surefire-reports') for the reports parameter, which is useful but not substantial. It does not compensate for any gaps because there are none, so a baseline 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?

The description states a specific verb ('runs flake-detector's gate') and a specific resource ('directory of JUnit XML reports'), and explains the exact decision logic (which failures block, which do not). It clearly differentiates from siblings like flake.rank and flake.explain by focusing on build gating.

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 clearly conveys the context of use (deciding whether failed tests block the build) through both the title and the explicit behavior description. However, it does not explicitly mention alternatives or exclusions, so it stops short of a 5. An agent can infer this is the tool for build-block decisions, but there's no guidance on when to prefer it over other flake tools.

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