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

Annotations already declare readOnlyHint, idempotentHint, non-destructive, and openWorldHint=false, so the safety profile is fully covered. The trailing "Read-only" merely repeats readOnlyHint and earns no credit. The description adds little behavioral context beyond the schema-documented URL constraint (only https://api.ucoz.net/{module}-openapi.yaml accepted), leaving it at a baseline 3.

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 front-loaded sentence with no filler, cleanly ordered purpose-then-capabilities-then-safety. It loses a point only because the closing "Read-only" is redundant against the annotations and could be dropped without loss.

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 5-parameter, enum-driven tool with 100% schema coverage and no output schema, the three modes are adequately described and it notes that fetch_spec returns a full specification. It could still say more about the shape/limits of returned specs (e.g. that results are YAML text), but nothing an agent needs to select or invoke it is missing.

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%, so the schema already documents all five parameters including the enum, ranges, and URL format restriction. The description contributes no additional parameter detail (no default hints, no interaction notes between action and module/query), so the baseline 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?

States a specific verb and resource ("Looks up the uCoz uAPI OpenAPI specifications") and enumerates its three modes — list, search, fetch — each mapping directly to an action enum value. No sibling tool provides documentation lookup, so it is trivially distinguished from the *_read/write/delete family.

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 describes what the tool does but never states when to reach for it (e.g. before invoking a uAPI method) or any exclusions. Usage is only implied by the action enum in the schema, not spelled out in prose. No alternatives exist among siblings, so the omission is less severe, but explicit guidance is absent.

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