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

Annotations cover the safety profile (readOnly, non-destructive, closed-world), and the description still adds valuable context: free, no API key, 0 units, public rules only, server-side guardrails remain authoritative, and the exact return shape. It stops short of describing versioning semantics or refresh behavior, so not a 5.

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?

Front-loaded with the WHEN directive and information-dense throughout; every clause carries content. It is a packed run-on spanning several ideas, which slightly hurts scanability but wastes no 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?

No output schema exists, and the description compensates by outlining the returned object structure and the domains covered. For a single-optional-parameter read tool with full annotations, nothing an agent needs to invoke 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 coverage is 100% and the enum already enumerates all domains, including the 'omit to receive all domains' behavior that the description repeats. The description adds no filter syntax or semantics beyond what the schema documents, 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 action (read a versioned playbook of best practices) and the exact resource, plus what it contains (public MCP/API rules, no tenant data). It is immediately distinguishable from every sibling, which are all task-specific domain tools rather than meta-guidance.

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?

Gives explicit invocation timing: call it FIRST on server discovery, and again if cached instructions may be stale. That is a clear when-to-use trigger that no other sibling provides, and it implicitly excludes routine data operations.

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