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

Annotations already cover read-only and idempotent; the description adds the decision taxonomy (match / mismatch / unknown) and the critical caveat that unknown includes address-lookup-table accounts and is not a safety signal. That is genuine behavioral context an agent needs before trusting the result, though output shape beyond 'decision' is not described.

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 purpose is front-loaded in four words, and the long parenthetical lists of supported opcodes are skimmable and earn their space by defining decode coverage. Slightly dense with semicolon-chained clauses, but no sentence is padding.

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 6-parameter tool with no required params, nested intent object and no output schema, the description covers mode selection, parameter meaning and the interpretation of the returned decision. It would be stronger if it stated that parameters are conditionally required per mode (nothing is marked required in the schema).

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 83% so the baseline is 3, and the description improves on it by explaining mode-exclusive parameter sets — data is EVM-only, transaction is Solana-only, contract is the transaction's `to` field. It also clarifies intent as a declaration of what you believe you are doing rather than echoing the calldata, which the schema alone does not make obvious.

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 — decode EVM calldata / Solana transactions and compare against declared intent — with the one-line framing 'Anti blind-signing' making the goal plain. It enumerates supported call types, so an agent can tell this apart from siblings like check_payment_request or payment_decision without opening a schema.

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 concrete routing rules: EVM uses intent + contract + data, Solana uses network:'solana' + transaction instead of data. It also states the action consequence ('do not sign' on mismatch) and warns that unknown is not safe. It stops short of naming sibling tools or stating when not to use it.

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