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

Beyond the annotations (readOnly=false, destructive=true), the description discloses critical behaviors: over-cap declines at Stripe without human click, fails closed if Stripe isn't Connect+Treasury+Issuing, no KYC collection, no Mercury opening, and per-call manager approval with no standing grant. No contradiction with annotations.

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?

Despite its length, the description is front-loaded with purpose and each sentence earns its place: use cases, failure mode, exclusions, routing, and the sensitive-tier approval rail. The paragraph breaks and routing labels make it scannable.

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 sensitive financial mutation with no output schema, the description covers what happens on success (card is the yes), on over-cap, when Stripe setup is wrong, and confirms the approval mechanism. It also tells the agent where to get status, making it complete for selecting and invoking correctly.

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 100%, so the schema fully documents all six parameters, including defaults and cents conversion. The description's example repeats the schema's own $100/month = 10000 example; 'network enforces' adds behavioral context but does not change parameter meaning, so it stays at the baseline 3.

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: 'Grant or raise this company's spend envelope' via a Stripe Issuing card with a network-enforced monthly spending_limit. It explicitly distinguishes itself from siblings by naming get_spend_envelope for status and start_company_receive/Allow-always as things it is not, so an agent can select it unambiguously.

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?

It gives explicit when-to-use criteria (founder granting a cap, raising it, setting MCC allow/block lists) and explicit exclusions (not start_company_receive, not Allow-always) plus status routing to get_spend_envelope. It even instructs the agent to call on the first clear ask and not re-ask in chat, which removes ambiguity about trigger timing.

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