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

Annotations already declare non-read-only, open-world, non-idempotent, non-destructive. Beyond that the description discloses the return contract (signed APPROVED/DENIED token), the gating rule for releasing funds, and the non-custodial posture ("sebbi.pro never holds the money") — genuinely useful behavioral context. It omits retry/idempotency implications and auth expectations for api_key.

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?

Four short sentences, zero waste, with the core action and the decision-token outcome front-loaded. Every sentence 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?

The request→decision→release workflow is covered and the return value is described in lieu of an output schema, but with 6 parameters at 17% coverage the description leaves the majority of the input contract undocumented and says nothing about failure modes or repeated-call behavior.

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 only 17% (just "Amount in pounds"), so the description carries the burden — yet it explains none of api_key, agent, payee, reason, or currency. An agent gets no guidance on payee format, agent identity, or currency default (implied GBP by the amount unit).

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: ask sebbi.pro to approve a payment before an agent makes it, and returns a signed APPROVED/DENIED token. The scope is unambiguous, but it never names the adjacent siblings (sebbi_spend_verify, sebbi_spend_policy) that an agent must choose between.

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?

"Ask ... before an AI agent makes it" plus "Only release the money if it is APPROVED and spendable" gives a clear trigger condition and a clear follow-up rule. It stops short of stating when NOT to call it or explicitly routing to sebbi_spend_verify for token validation.

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