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

Annotations cover the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false), so the bar is lower. The description adds genuine behavioral context beyond them: the retest inherits the original test's URL, custom goal, system prompt, and inbox configuration, which tells the agent the verification covers the identical flow. It does not spell out that each call creates a fresh job/run, which would complete the non-idempotency picture.

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?

Two sentences, zero waste, front-loaded with the action and followed by the use case and the config-reuse behavior. Every clause 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?

Given the single-parameter schema, full annotation coverage, and the presence of an output schema (so return values need not be described), the description supplies everything an agent needs: what it does, when to call it, and what state it preserves.

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?

With a single parameter at 100% schema description coverage, the schema already documents jobId and its origin (submit_test or a prior retest_job). The description adds no syntax or format detail beyond that, so the 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+resource+scope: re-run an existing test job against the latest deployment. This is clearly distinguishable from submit_test (which creates a new test) and get_test_results (which reads results), so an agent can tell the three 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?

Explicitly names the trigger condition (after pushing a fix surfaced by get_test_results) and the goal (verify the bug is gone), and names a sibling tool. It stops short of stating when NOT to use it (e.g., for a brand-new flow, use submit_test), but the context is strong.

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