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

With no annotations, the description carries the behavioral burden. It discloses that the tool does not spend credits, returns 'ok + valid', supports sandbox/live tokens, and offers an offline verification path. It does not describe invalid/expired JWT behavior, but the disclosed side-effect and output profile is unusually clear.

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?

Three short sentences deliver the operation, scope, output, side-effect profile, and an alternative with zero filler. Every clause earns its place.

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 one-parameter, no-output-schema tool, the description is complete: it states what is verified, which token types are accepted, what is returned, that it is non-spending, and how to verify offline. An agent has enough context to select and invoke it.

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%: rider_token is described as 'Rider JWT to verify'. The description adds that tokens can be sandbox or live and that verification does not spend, but it does not add protocol-level meaning beyond the schema, so the baseline 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 opens with a specific verb and resource, 'Verify a rider JWT', and narrows scope with 'sandbox or live'. This clearly differentiates it from sibling tools like issue_rider (which creates tokens) and verify_trust (which verifies a different entity).

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 gives an explicit alternative ('Offline alternative: GET /.well-known/jwks.json (ES256)') and a safety qualifier ('No spend') that helps an agent decide to call it for non-mutating verification. It stops short of full when/when-not conditions, so it loses one point.

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