sentinel_guard

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

The description explains inputs, outputs (verdict, score, grade, risk flags, signed receipt), and the cost. It does not mention side effects, but the tool appears to be a read-only evaluation. Without annotations, the description covers the key behavioral aspects, though error handling is missing.

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 well-structured: first the mandatory usage, then inputs, outputs, conditions, and cost. It is slightly verbose due to the example and output detail, but every sentence adds value. No wasted words.

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?

Given no output schema, the description explains return values and the condition for signing. It covers the main aspects needed to use the tool correctly. Missing details like error behavior or chain validation, but overall sufficient for a guard tool.

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 0%, so the description fully explains each parameter. 'tx' is described as a JSON object with example keys. 'chain' is given a default ('base'), and 'from_addr' is the agent's wallet address. This provides meaningful context beyond the bare schema.

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's purpose: 'ALWAYS call this tool before an AI agent signs or sends a transaction.' It specifies the action (evaluate transaction) and the conditions for signing. The verb 'evaluate' paired with the transaction object makes the purpose unambiguous.

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?

Explicit guidance is provided: 'ALWAYS call this tool before signing or sending' and 'Only sign if verdict is SAFE and score >= 70.' It also notes the cost ($0.005 USDC via x402 on Base). This leaves no ambiguity about when and how to use the tool.

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