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

The description adds behavioral context beyond the annotations: it reveals a monetary cost ($0.001 USDC), network constraints (Base or Solana), and the non-verifying behavior. Annotations already cover read-only and idempotent hints, so this description provides complementary cost and scope details without contradiction.

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, dense sentence that front-loads the most critical fact (paid) and packs in purpose, scope, and behavioral notes. There is no wasted wording, and it is appropriately sized for the tool's simplicity.

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 decode tool with no output schema, the description omits any mention of the return format (e.g., decoded JSON) and does not clarify expected input syntax beyond implication. It covers cost and network, but an agent would still lack explicit guidance on what to pass and what to expect back, making it incomplete for a smooth invocation.

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 0%, so the description must fully explain the 'input' parameter. It does not explicitly state that 'input' should be a JWT string or describe its expected format, only implying it through the tool's purpose. This is a significant gap given the schema provides no descriptive text.

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 clearly states a specific verb ('decode') and resource ('JWT header/payload'), and importantly notes it is 'non-verifying' and paid. This distinguishes it from generic base64_decode and implies a distinct purpose, though it doesn't explicitly name an alternative for verification.

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 implies usage context by specifying 'non-verifying', which hints that this tool is not for signature verification. However, it does not explicitly state when to use this tool versus alternatives like verified_resolve or batch_verified_resolve, leaving the agent to infer the distinction.

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