run_tests

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It only says tests are run; it does not mention side effects (e.g., file changes, building), required environment, return values, or exit-code behavior. An agent cannot predict what happens on success or failure.

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 zero waste. It states the core purpose immediately and avoids unnecessary detail. This is appropriate conciseness for a narrowly scoped tool.

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 tool with only two optional parameters and no output schema, the description covers the basic action but omits critical context such as how results are reported, whether a successful run produces output, or any prerequisites (e.g., project must be set up). The absence of annotations makes this gap more significant.

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?

The schema already describes both parameters at 100% coverage, so the baseline is 3. The description adds no extra meaning; 'optional pattern matching' aligns with the test_pattern parameter, but the schema already explains it. No value is added beyond the structured definition.

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 the verb 'run' and the resource 'test suite', and 'only' signals a narrow scope that differentiates from check/lint/typecheck siblings. However, it does not explicitly name alternative tools or explain which checks are excluded, so it stops short of full clarity.

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?

There is no guidance on when to use this tool versus its siblings. 'Only the test suite' implies it is not for linting or typechecking, but the description never states that explicitly, nor does it offer conditions or exclusions. The agent is left to infer usage from the name alone.

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