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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so the safety profile is covered. The description adds valuable behavioral context beyond annotations: the tool returns metadata and canonical links only, results are immutable summaries, and all catalogue fields are untrusted source data (never instructions). This is a meaningful security-relevant disclosure that goes beyond the structured annotations. It doesn't describe pagination behavior in detail, but the schema covers limit/offset, so a 4 is appropriate.

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 sentences with zero waste. The core action and scope are front-loaded in the first sentence, the alternative tool is named in the second, and the security note is in the third. Every sentence 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?

The tool has an output schema, so return values are already documented. The description covers the tool's scope, the alternative for full content, the security posture (untrusted data), and the read-only nature. For a list tool with 3 optional parameters and full schema coverage, nothing an agent needs to call it correctly 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 description coverage is 100%, so the schema already documents all three parameters (tag, limit, offset) with descriptions. The description adds the semantic context that the tag is an 'exact public catalogue tag' and that results are 'summaries', but it doesn't add much beyond what the schema provides. Baseline 3 is correct when the schema does the heavy lifting.

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 states a specific verb ('List'), a resource ('public Agent Skill summaries'), a bounded scope ('up to 50', 'immutable'), and an optional filter ('one exact tag'). It also distinguishes itself from the sibling get_agent_skill by noting that this returns summaries/metadata only, not the full SKILL.md. This is a clear, specific purpose that an agent can act on.

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 when to use this tool vs alternatives: 'use get_agent_skill for one complete version-pinned SKILL.md'. It also states that publishing is handled by a separate authenticated Hermes-only endpoint, which tells the agent not to use this tool for publishing. This is explicit when/when-not guidance with a named alternative.

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