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

With readOnly/idempotent/destructive annotations already covering the safety profile, the description still adds non-obvious behavior: it does not execute the tests it builds, and its checks cover observed calls and typed arguments rather than backend effects or independent permission enforcement. That last sentence usefully bounds what the tool actually verifies.

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?

Four short sentences, front-loaded with what is produced and then the prerequisites and scope limits; every sentence adds a constraint rather than restating the title. Slightly dense but no 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?

An output schema exists, so return-shape detail is unnecessary, and the description still names the produced file. Combined with the prerequisite statement and the explicit limits on what is not validated, an agent has enough to decide and invoke; the missing piece is sibling differentiation.

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?

Top-level schema description coverage is 0% for the single required `tests` parameter, but the description conveys the cardinality (1-20 checks) and hints at the rule semantics (observed calls vs typed arguments). The nested schema already carries description text for id, name, rule, and prompt, so the description only partially compensates.

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 gives a specific verb+resource with scope ("Build 1-20 tool invocation checks for an authorized staging agent") and names the output artifact (tool-tests.json). It does not, however, distinguish itself from the similarly named sibling build_test_pack, leaving the agent to infer the split from the name alone.

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?

It states preconditions (a one-time dispatcher capture is required, run via the free PromptBrake Action, no license needed) which is real usage context. But it never says when to prefer this tool over build_test_pack or the other siblings, and gives no when-not guidance.

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