revoke_token_approval_evm

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

The description discloses the primary side effect—setting allowance to 0—which is essential behavioral context. However, it does not mention that this is an on-chain transaction requiring gas, wallet confirmation, or that it permanently alters state. With only 'openWorldHint: true' as annotation, the description adds some value but leaves the full side-effect profile implicit.

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 description is a single sentence that front-loads the action and includes a clarifying parenthetical. Every word earns its place with no redundancy or unnecessary detail.

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?

The description explains the tool's purpose and effect, and the schema fully documents inputs. However, it does not mention return values (e.g., transaction hash), network side effects, or execution context. For a relatively simple tool with full param documentation, this is adequate but not thorough.

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 descriptions cover all three parameters (chainId, spender, tokenAddress) at 100% coverage. The tool description does not add any additional parameter semantics beyond what the schema provides, so the baseline score of 3 is appropriate.

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 uses a specific verb 'Revoke' and names the resource 'approval for an ERC20 token from a spender', explicitly stating the effect: '(sets allowance to 0)'. This clearly differentiates it from approve-family tools and other token operations, despite not explicitly mentioning EVM (the name carries that context).

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 description provides no guidance on when to use this tool versus alternatives like 'approve_token_evm', 'approve', or 'revoke_approval'. There are no prerequisites, exclusions, or context about when to prefer this tool, leaving the agent without decision support.

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