wallet_sign_transaction

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

With no annotations, the description carries the full disclosure burden. It does usefully disclose the key non-broadcast side effect and the chain-specific input format, but says nothing about the password/decryption requirement at call time, failure modes, or what the signed output looks like (no output schema to fall back on).

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 tight sentences, with the decisive constraint ('does not broadcast') front-loaded before the chain-specific input details. No filler.

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 tool with a nested transaction object, no annotations, and no output schema, the description is adequate on inputs but leaves the return value (signed payload format) and the decryption/password behavior unaddressed, which an agent needs to chain this with wallet_send_transaction.

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 baseline is 3, but the description goes further by specifying 'standard tx fields' for EVM and 'base64-serialized' for SVM on the ambiguous nested 'transaction' object. That adds format-level meaning the schema's terse summary does not fully pin down.

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 ('Sign a transaction') plus the scope ('with a stored wallet'). The parenthetical '(does not broadcast)' implicitly separates it from wallet_send_transaction, but the sibling is never named, so differentiation relies on the agent making the connection itself.

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?

Gives clear context: sign-only, no broadcast, with per-chain input expectations. It stops short of explicitly routing the agent — it never says 'use wallet_send_transaction if you also want to broadcast' — so the when-not guidance 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.