validate_eip712_permit

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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), so the bar is lower. The description still adds real value by disclosing the exact validation semantics: field presence/well-formedness plus a deadline-vs-now_timestamp comparison, and that violations are returned rather than throwing. It never says whether the EIP-712 signature itself is recovered/verified, which is the one notable ambiguity for a tool named 'validate_eip712_permit'.

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?

Two sentences, fully front-loaded: the validation contract first, the return value second. No filler and every clause carries information.

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?

With an output schema present, the description need not explain is_valid/violations in detail, and it covers both inputs and the validation rules. The only gap is the ambiguity over signature verification, which leaves a small hole for a tool whose name emphasizes EIP-712 signing.

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 100%, so the baseline is 3, but the description adds meaning beyond the schema by enumerating the required permit subfields and clarifying that now_timestamp is caller-supplied and used specifically as the deadline comparison point. That is a genuine increment over the schema text.

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 (validate) and a precise resource (EIP-2612 permit), then enumerates the concrete checks applied. The narrow domain immediately separates it from siblings like check_mandate, validate_mandate_expiry, and verify_x402_signature without needing to name them.

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 validation rules imply the intended use (pre-flight checking of a permit before submission), but there is no explicit statement of when to call this versus verify_x402_signature or check_mandate_expiry, nor any exclusions. Usage is inferable rather than stated.

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