run_tests

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

With no annotations, the description bears full responsibility for disclosing behavioral traits. It only says 'return structured results' but omits critical details like error behavior, blocking vs non-blocking execution, permissions required, or performance characteristics. The parameter descriptions add some detail but the tool description itself is insufficient.

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 sentence, which is concise but lacks structure and key information. It is appropriately short but at the expense of completeness. A slightly longer description with bullet points would improve clarity.

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 12 parameters, no output schema, and no annotations, the description is overly minimal. It does not explain return values, error handling, prerequisites (e.g., playwright installation), or the effect of parameters like wait or headed. The description fails to provide a complete picture for a complex tool.

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 92% (high), so the schema provides detailed parameter semantics. The tool description adds no additional parameter meaning. Baseline 3 is appropriate since the schema already does the heavy lifting and the description does not detract.

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 clearly states the tool runs Playwright tests and returns structured results, which distinguishes it from sibling tools that retrieve failures or status. However, it doesn't explicitly differentiate itself from other sibling tools that might also involve running tests (e.g., list_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?

No guidance is provided on when to use this tool versus alternatives like get_run_status. The wait parameter hints at background runs but is not described in the tool description itself. The agent is left to infer usage context from the parameter descriptions.

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