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

No annotations are provided, so the description carries the full behavioral burden, and it discloses nothing: no statement about whether the operation is read-only, whether errorText is stored or transmitted externally, whether the result is cached, or what kind of output to expect. "diagnostic" hints at a non-mutating analysis step but never confirms it.

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?

It is short, but the brevity comes from under-specification rather than efficient phrasing — the single fragment is a namespaced identifier with a redundant parenthetical. Nothing is front-loaded because there is no substantive content to order.

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 output schema and no annotations, the description should explain what the diagnosis yields and what the agent should do with errorText. It leaves the entire behavioral and output contract unspecified, so an agent must guess before invoking.

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?

There is exactly one parameter with 100% schema description coverage ('Sanitized error or log excerpt.'), so the schema already documents the input fully. The description adds no meaning about format, size limits, or what makes an excerpt useful, which is the baseline-3 outcome when schema coverage is high.

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 is essentially the fully-qualified tool name plus the word "diagnostic" — it restates the identifier rather than stating a verb and resource. An agent cannot tell from this text whether it analyzes error text, returns fix suggestions, or produces a report, nor how it differs from sibling tools like fix.suggest or shared::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 condition for selecting this over fix.suggest, env.preflight, or runtime.readiness.diagnose, and no prerequisites. The word "diagnostic" implies a vague context but names no trigger or exclusion.

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