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

With readOnlyHint=true already supplied, the description still adds real behavioural content: the plan is ordered and exact, and the caller must not discover or re-derive the transaction list. Those are genuine planning contracts beyond the annotations. It stops short of stating that no signing or broadcasting occurs, or how gas/nonce are handled, which would have made it a 5.

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 short sentences, both front-loaded with the essential facts: what is produced and how the caller must treat it. There is no filler or restatement of the title.

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?

An output schema exists, so return-value detail is not required, and the description covers the plan-building contract and ordering constraint adequately for a three-parameter tool. The remaining gap is edge-case behaviour (mixing multiple chains or tokens, or what happens when a revocation is already in place), which is minor but not covered anywhere else.

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 67%, so the schema documents sender, chain_id and the token/spender pair at a basic level. The description adds the semantic that each approvals entry becomes an approve(spender, 0) call, clarifying what token and spender mean in the revocation context, but it says nothing about chain_id handling or multi-chain batching, so it is a modest gain over the 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 names a specific verb ("Prepare") and a concrete resource ("every approve(spender,0)") and states the output artefact: "an exact ordered multi-transaction execution plan". This distinguishes it cleanly from neighbouring planners such as prepare_transfers or prepare_wrap_unwrap without requiring the schema to be opened.

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?

Usage is implied: it is the tool to call when a wallet needs a revocation plan and must not build the list itself. However, there is no explicit when-not guidance, no named alternative for related flows (e.g. prepare_transfers for moving tokens), and no prerequisite stated such as requiring the approvals to already exist on-chain.

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