Where the published artefacts live

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so no safety contradiction exists. The description adds meaningful behavioral context beyond annotations: the server may be mounted under a path prefix, and the returned URLs are authoritative for this instance. This helps the agent understand why hardcoding paths is unsafe.

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?

Two sentences with no wasted words. The first sentence front-loads what the tool returns, and the second provides the rationale for using it over assumptions. Every phrase earns its place.

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 no-parameter, read-only endpoint discovery tool, the description is nearly complete: it lists the artefacts whose URLs are returned, explains why the tool exists, and clarifies the server-authoritative nature. It doesn't specify the exact response shape or keys, but the artefact list gives an agent sufficient expectation of what it will receive.

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 tool has zero parameters and schema coverage is 100% vacuously, so there is no parameter information missing. The description doesn't need to define inputs, and the baseline for zero-parameter tools is 4.

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 tool returns absolute URLs for specific artefacts (stylesheet, token files, behaviours bundle, documentation site), which distinguishes it from siblings that fetch content or tokens. The verb is implicit but the resource scope is concrete and unambiguous.

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 to use this tool instead of assuming paths, and explains why: the server may be mounted under a path prefix that only the server knows. It doesn't name sibling alternatives or give when-not-to-use conditions, but the context is clear enough for an agent to select it over content-fetching tools.

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