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

readOnlyHint=true is consistent with a tool that only produces typed data and does not sign or submit anything, and the description reinforces this by telling the caller signing happens locally. It adds genuinely useful behavior beyond the annotation: the default spender (protocol diamond), the deadline-based validity, and the shape of the returned transferAuthorization template. It stops short of noting any chain/domain constraints.

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?

Three tight sentences with zero filler, front-loaded with the operation and standard, followed by usage and the return shape in priority order. Every sentence earns its place.

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 an 8-parameter tool with no output schema, the description compensates by summarizing the return value (typedData plus transferAuthorization template) and the wiring into send_meta_transaction. No output schema exists, so this is adequate; only minor details (domain/chain nuances) are left unstated.

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%, so the baseline is 3. The description loosely ties value, signerAddress and deadline together and restates the default spender, but that default is already documented in the schema, so it adds little meaning beyond what structured fields already supply.

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: 'Generates EIP-712 typed data for an EIP-2612 Permit.' The standard is named, which implicitly separates it from the sibling sign_receive_with_permit2/erc3009/dai_permit tools, but it never explicitly contrasts them, so an agent must infer the distinction from the protocol name alone.

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?

Provides concrete usage context: sign locally with the wallet, then attach the resulting signature to send_meta_transaction.transferAuthorizations. It names the downstream tool and the field to populate, which is strong routing. It does not state when NOT to use this versus the other permit variants, so it falls short of a 5.

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