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

The annotation readOnlyHint: true already covers the read-only nature. The description adds context that built-in rules are included unless filtered out and that project context is required, but does not mention pagination or return format. This is a reasonable addition beyond the annotation without contradiction.

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 three tight sentences, front-loaded with the main action, and contains no redundant or filler content. It efficiently packs purpose, behavior, and usage guidance.

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 list operation with no output schema, the description covers the key aspects: what it lists, scope, filtering behavior, and distinguishing from a sibling. It does not state the return structure, but that is not mandatory here; still, a brief mention of the result type would have made it fully complete.

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%, so the baseline is 3. The description subtly hints at the isBuiltIn filter ('unless you filter it out') and the project context requirement, which adds slight value beyond the raw parameter docs. No contradiction.

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 lists Smart Mock matching rules for one mock server, defines what those rules do, and explicitly distinguishes it from the org-wide variant. This gives a precise, unambiguous 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?

It explicitly tells the agent when to use this tool (for one mock server) and when to use the alternative (list_org_smart_mock_rules for org-wide), and also notes that project context is required. This is strong, actionable guidance.

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