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

Annotations already declare readOnlyHint=true, and the description adds that no API key is needed, confirming a safe read operation. It explains the return options (full guide or version string) and the caching optimization. Minor gap: could mention if the operation is fast or has side effects, but overall good.

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?

Three well-structured sentences. The first identifies the tool and its content, the second gives usage context, the third explains the parameter. No wasted words.

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?

Given the tool's simplicity (one boolean param, no output schema), the description covers all essential aspects: what it returns, when to use, how to use the parameter, and what the guide contains. No gaps for effective agent invocation.

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% for the single parameter. The description adds meaningful context by explaining the caching use case for version_only, going beyond the schema's basic description. It clarifies why one might use this parameter.

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 identifies the tool as retrieving the relay's SKILL.md guide, explaining its content (Homespun workflow, events vs records, schema grammars, poll loop). The title 'Get Skill Guide' aligns well, and the description distinguishes the version_only parameter's purpose.

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?

Explicitly states when to use: 'when working out how the other tools fit together, or to refresh a cached copy.' Also mentions it needs no API key, and gives guidance on using version_only to check cache freshness.

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