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

Annotations already establish readOnlyHint=true, destructiveHint=false and a closed-world scope, so the safety profile is covered. The description adds genuinely useful non-annotation context (free during validation, no key/credits/wallet, source and input limits apply), but says nothing about which credential patterns are matched, what the markers look like, or whether surrounding text/structure is preserved.

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?

Four short sentences with the purpose front-loaded and no padding. The telegraphic pricing/limits fragments are efficient, though they crowd out more useful invocation 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?

An output schema exists so return values need not be explained, and annotations cover safety. Still, for a redaction tool the agent lacks sibling differentiation and any sense of pattern coverage or marker format, leaving the definition minimally adequate.

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%, so the schema documents requestId and maxPriceMicroUsd as ignored legacy fields. The description's 'Existing source and input limits apply' is vague and adds little beyond the schema's maxLength of 100000; the nested input.text object itself remains undocumented in the description.

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 verb+resource: 'Replace detected credential patterns with redaction markers.' An agent knows exactly what transformation is performed. However, it never distinguishes itself from the sibling security_secret_scan, so the agent must guess which of the two to pick.

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 spends its budget on pricing ('FREE during validation. No key, credits or wallet') rather than on when to use this tool versus security_secret_scan or any alternative. No conditions, prerequisites, or exclusions are given, leaving usage entirely to inference.

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