List Test Runs

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

With no annotations, the description must carry the burden of behavioral disclosure. It states the tool reads from a specific directory and filters by file type, implying a read-only operation. However, it does not mention whether the list is sorted, what happens if no files are found, or any access restrictions besides 'approved'. This is adequate but not rich.

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 that gets straight to the point: 'Find available Playwright JSON and JUnit test-result files in the approved reports directory.' No redundancy or fluff; every word contributes.

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 simple parameterless list tool, the description is complete enough. It specifies the exact files sought and the directory. Without an output schema, it could benefit from mentioning the return format (e.g., list of paths), but for a 'find' operation the output is reasonably inferable. The context of sibling tools suggests it is a discovery step, which is adequately conveyed.

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 tool has zero parameters, so the baseline is 4. The description adds no parameter-specific semantics because there are none to explain. It briefly hints at the scope (directory) but does not need to elaborate further.

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's function: 'Find available Playwright JSON and JUnit test-result files in the approved reports directory.' The verb 'find' plus the specific resource (test-result files) and location (approved reports directory) fully distinguish it from sibling tools like get_test_run_summary or analyze_test_failures, which serve different purposes.

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 usage: it is for locating available test result files before running analyses or summaries. However, it does not explicitly mention when to prefer this over siblings or provide exclusions. Given the sibling tools exist, some guidance on 'use this to discover files before invoking summary/analysis' would have been helpful.

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