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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false), so the bar is lower. The description adds genuinely new behavioral context: the operation is deterministic, ultra-fast, and is a paid call ($0.001 USDC on Base), which tells the agent this is a metered x402-style endpoint. It does not mention rate limits or output determinism caveats, but adds real value beyond the annotations.

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 and short, but the price is stated twice ('$0.001' in the opening clause and again as 'Price: $0.001 USDC on Base'). That duplication is waste in a two-sentence description and slightly dilutes the structure.

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 one-parameter tool with full schema coverage and an existing output schema, the description need not explain return values. It communicates purpose, safety, and payment model adequately; only usage routing against siblings 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?

With a single parameter at 100% schema description coverage ('Raw text context to scrub'), the schema already carries the meaning. The description adds nothing about the text parameter itself, 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 verb and resource - a 'scrubber' for 'raw agent context windows' targeting prompt-injection and wallet-drainer payloads. This distinguishes it from siblings like security_evm_calldata_firewall (calldata) and security_url_threat_check (URLs), though it does not explicitly name those alternatives.

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 phrase 'for raw agent context windows' implies a usage context, but there is no explicit when-to-use, when-not-to-use, or comparison against the security_* and sanitize siblings an agent would be choosing between. Guidance is left entirely to inference.

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