upgrade

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

With no annotations, the description fully describes behavior: returns Stripe Checkout URL for human payment, no password needed, and returns billing-portal for existing Pro accounts. It discloses the side effect of raising quota and the interactive nature of the process.

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 sentences, each serving a purpose: first states overall goal, second explains the Stripe URL usage, third adds the alternative case for existing Pro accounts. Very concise and well-structured.

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 zero-parameter tool with an output schema, the description covers all necessary context: what the tool does, what it returns, and edge-case behavior. No gaps identified.

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?

There are zero parameters, so schema coverage is 100%. The description does not need to add parameter information. Baseline for 0 parameters is 4, and the description is sufficient.

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 the tool returns a URL to upgrade the account to Pro, with specific handling for already Pro accounts (billing-portal URL). The verb 'upgrade' and resource 'account to Pro' are precise, and the two cases are well delineated.

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 for upgrading accounts, but lacks explicit guidance on when to use this tool versus alternatives. Siblings are notify and check_status, which are unrelated, so no comparative context is provided.

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