record_comparison

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

The annotations already indicate this is not read-only, not idempotent, and not destructive. The description merely restates the write nature via 'persist' and adds little beyond that: no mention of whether existing comparisons are overwritten, whether duplicates are created, what prerequisites exist, or what side effects occur.

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?

A single sentence that front-loads the primary action and then gives the read-only alternative. Every word earns its place; there is no redundancy or filler.

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?

The input schema is complex (oneOf with measurement and runtime_resource variants), but the description does not explain what 'recorded comparison' means, how it relates to compare_run_sets beyond read-only preview, or what lifecycle state this creates. Given the high complexity and sparse description, the agent lacks enough context to invoke it confidently.

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 0%, yet the description provides no information about the 'request' parameter or how to construct it. The agent is left to infer from the schema alone that the request is a CompareRunSetsRequest, and the description does not compensate for the absent 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 ('Persist') and resource ('a reviewed comparison'), and explicitly contrasts with compare_run_sets for read-only preview. It is clear in intent and distinguishes this tool from the most relevant sibling, though 'reviewed comparison' is somewhat abstract.

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?

Explicitly states when to use this tool versus the alternative: persist a reviewed comparison, and use compare_run_sets for read-only preview. This gives the agent direct routing guidance with no need for inference.

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