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

Beyond annotations (idempotentHint=true, readOnlyHint=false), the description adds billing details (500 micro-dollar credits per call), the need for a private auth header, and that a new requestId is a new billable operation. This clarifies cost and idempotency implications, which the annotations only hint at.

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 concise (four sentences) and front-loaded with the primary purpose. The billing and prerequisite details are presented efficiently without redundancy. It earns a 4, not 5, because the usage notes could be slightly more compact.

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 covers the essential operational context: paid service, preparation step, auth requirement, and recovery behavior. The output schema is provided separately, so no need to explain return values. It does not mention how the tool interacts with security_secret_scan, but that is not critical for 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 67% (requestId and maxPriceMicroUsd have descriptions; input does not). The description indirectly clarifies requestId (persist from prepare) and maxPriceMicroUsd (recovery only when 0), but these are already in the schema. It does not add new meaning for the input object, so it stays at the baseline.

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 action ('Replace detected credential patterns with redaction markers') with a specific verb and resource. It distinguishes from the sibling security_secret_scan (scan vs. redact) without being ambiguous.

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?

Provides explicit prerequisites: first use agent_utilities_prepare, requires existing credits and a private Authorization header. Also explains recovery usage (reuse requestId). Does not explicitly name alternatives or exclusions, but the context is clear enough for an agent to know when to invoke.

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