compare_run_sets

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

The description adds valuable behavioral context beyond the annotations by stating that the operation has 'no persistence' and is a 'preview'. This goes beyond the readOnlyHint and idempotentHint, clarifying that it does not save anything. It is concise but informative.

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 exactly two sentences, front-loading the core purpose and then pointing to the alternative. Every word earns its place, with no redundancy or filler. This is an ideal structure for a tool description.

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 that annotations cover safety and an output schema exists, the description is minimally adequate for a read-only preview tool. However, it fails to explain what 'compatible' cohorts means, what prerequisites exist (e.g., run sets must be frozen), or any details about the comparison scope. The description is complete enough for a basic understanding but lacks depth for this complex oneOf schema.

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 has 0% description coverage and the description provides no information about the 'request' parameter or its sub-fields. While the schema names parameters like 'baseline_run_set_id' and 'candidate_run_set_id', their meaning, relationships, and selection criteria are unexplained. The description does not compensate for the lack of parameter documentation.

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 uses a specific verb 'preview' and resource 'compatible frozen cohorts', clearly indicating it does a dry-run comparison without saving. It also explicitly differentiates from the sibling tool 'record_comparison', which is used to persist comparisons. This makes the tool's purpose unmistakable.

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 explicitly tells the agent to use 'record_comparison' when persistence is needed, providing a clear alternative and exclusion. It also implies this tool is for previewing, giving clear contextual guidance on when to use it.

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