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

With no annotations, the description carries the full behavioral disclosure burden and delivers strongly. It states the detection runs in-process offline with no API key (pure regex + Luhn check, no network), discloses that a configured SecretScan backend reroutes the scan and 'persists an audit record,' and describes the redaction token format. This gives an agent accurate expectations about execution mode, side effects, and network dependency.

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 bulk of the description is operational and worthwhile, with the core purpose front-loaded in the first sentence. All-caps emphasis like 'WORKS OFFLINE with NO API key' and 'BEFORE' adds assertiveness rather than information, and the sentence 'Catches the #1 real-world agent incident' is context rather than instruction — minor redundancy that keeps it from a perfect score.

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 no explanation, and the description covers the essential operational context: detection approach, execution mode (offline vs backend-routed), backend auditing, and the redact toggle's effect. Minor gaps remain, such as what happens when no secrets are found or how report-only output is structured, but these are partially covered by the output schema and the tool's simple two-parameter surface.

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% — text and redact are already documented in the input schema, including the redaction token examples. The description reinforces that behavior ('return a redacted copy', token names) but adds no new parameter semantics beyond the schema, so the baseline 3 is appropriate.

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 and resource: 'Scan a text payload (a prompt, an outbound API body, a file's contents) for secrets and PII ... and return a redacted copy.' This makes the operation's intent and scope unmistakable. It also positions the tool against its siblings by naming the exact incident class — content leaking to an LLM or external API — which differentiates it from network_scan and scan_skill without opening their schemas.

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 gives a clear, actionable 'when to use': any payload 'before it leaves for an LLM or external API,' framing it as the guardrail for the #1 real-world agent incident. It does not, however, explicitly state when not to use it or name alternative sibling tools, so it stops short of a complete guidance.

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