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

There are no annotations, so the description carries the full burden. It says 'Fetch' and 'persisted', which strongly implies a read-only operation with no side effects. However, it does not explicitly state that it is non-mutating, nor does it mention any rate limits, authentication requirements, or error conditions. Given the simple getter nature, this is adequate but not exhaustive.

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 two concise sentences, front-loaded with the primary purpose and followed by usage guidance. Every word adds value, with no filler or repetition. It is efficiently structured for quick comprehension.

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?

While the description covers the purpose and usage well, it leaves out an explanation for the required preset_id parameter and does not describe the return format (though no output schema exists). For a tool with no annotations and no output schema, the description should compensate for these missing details, which it only partially does.

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, so the description must explain both parameters. It mentions run_id as the identifier, but completely omits preset_id. An agent cannot infer what preset_id is for from the description alone, creating a significant gap in understanding how to properly invoke the tool.

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 verb 'Fetch', the resource 'Detect Agent investigation', and the key identifier 'run_id'. It also mentions the included 'full event transcript', making it distinct from sibling tools like list_detect_agents or run_detect_agent_investigation. The purpose is unambiguous and specific.

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 says 'Use after run_detect_agent_investigation reported timed_out, or to re-read an earlier investigation.' This provides clear, actionable guidance on when to invoke this tool versus alternatives, leaving no ambiguity about the intended use case.

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