compare_with_last_success

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

With no annotations provided, the description carries the full burden. It only states the comparison operation but omits behavioral traits such as whether it is read-only, what happens if no successful run exists, any required permissions, or the format of the comparison output.

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, front-loaded sentence with no extraneous words. It concisely conveys the core purpose.

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 low complexity (3 simple parameters, no output schema, no annotations), the description is adequate but incomplete. It does not describe the return value or behavior when there is no successful run, which are gaps for correct invocation.

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%, so the baseline is 3. The tool description adds context by clarifying that run_id is 'the failed run ID', which aligns with the schema. No additional meaning beyond what the schema already provides.

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 ('compare') and resources ('failed run' with 'last successful run') and context ('on the same branch'), clearly distinguishing from siblings like 'explain_failure_root_cause' or 'detect_flaky_tests'.

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 tool is used for comparing a failed run to a last successful run, but does not explicitly state when to use it over alternatives like 'find_regression_pr_or_commit' or 'suggest_fix_for_failure', nor provides any exclusions.

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