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

The description explicitly notes 'Does not itself perform the procedure,' which aligns with the readOnlyHint annotation. This reassures the agent that the tool has no side effects. While the annotation already conveys read-only behavior, the explicit human-readable statement adds clarity beyond the raw flag.

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 description is two sentences, concise and free of fluff. It front-loads the core purpose and adds a critical caveat in the second sentence. No unnecessary words or repetition.

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?

The description indicates the output will be 'instructions and resolved references', giving the agent an idea of what to expect. It does not specify output format, error conditions, or permissions, but given the simple read-only nature and the presence of sibling list tools, the context is reasonably complete for invoking the tool.

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?

All four parameters are described with useful context: name is 'as listed by list_pcd_skills', handle is 'your active deck handle', contract is 'Help mode — return the complete contract', and container_id is 'speeds up lookup, include if known'. These go beyond mere parameter names and provide actionable semantic meaning.

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 specific action: 'Retrieve a named skill’s instructions and resolved references.' This identifies the verb (retrieve) and resource (skill instructions). It also distinguishes itself from execution by adding 'Does not itself perform the procedure,' which separates it from any skill-running tool.

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 implies usage ('for the assistant to follow') but does not explicitly state when to prefer this tool over siblings like list_pcd_skills or create_pcd_skill. No direct comparison or conditional guidance is provided, so the context is only implicit.

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