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

No annotations are provided, so the description carries the full burden of behavioral disclosure, and it discloses nothing. It does not say whether the call is read-only, what the output looks like, whether it needs network access, or what limits apply to the error text.

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 single fragment is short but not informative — brevity here is under-specification rather than conciseness. There is no front-loaded statement of intent or outcome to justify the sentence's existence.

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 diagnostic tool with no annotations and no output schema, the description should explain what the diagnosis produces and when it applies. None of that is present, leaving the definition functionally empty.

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 coverage is 100%: errorText is documented in the schema as a 'Sanitized error or log excerpt' with an 8000-character cap. The description adds no syntax, format, or sanitization guidance beyond that, so the baseline of 3 applies.

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 only restates the tool name and adds the generic label '(diagnostic)'. It never states what the tool actually does with the errorText it accepts — no mention of root-cause analysis, fix recommendation, or log interpretation — so it cannot be distinguished from siblings like fix.suggest, env.preflight, or runtime.readiness.diagnose.

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?

There is no when-to-use guidance, no prerequisites, and no alternate-tool routing. An agent facing a runtime error has no basis for choosing runtime.diagnose over fix.suggest or env.preflight based on this text.

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