Activate AlzaSubscription

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

Annotations already declare destructiveHint=true and idempotentHint=false; the description adds that it starts a paid, recurring subscription and emphasizes the need for explicit confirmation. This goes beyond the annotations without contradicting them, though it could mention irreversibility or billing details.

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 compact and well-structured: purpose first, then safety warning, then prerequisites and parameter notes. Every sentence adds value with no redundancy.

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 high-impact mutation tool, it covers the essential context: what it does, safety confirmation, the token prerequisite, and parameter origins. With an output schema present, the return value is already documented, so nothing critical is missing.

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%, so baseline is 3. The description adds meaning by explaining that values carries payment/installment fields verbatim from the form response, and that the action must be copied from a prior tool response. This clarifies the data flow beyond the schema's generic descriptions.

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 verb 'Activate' and the resource 'AlzaSubscription', and explains it executes a server-provided form. It distinguishes itself from siblings by referencing subscription_overview and prepare_mutation, making its purpose unambiguous.

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 explicitly states when to use: only with explicit user confirmation after showing terms from subscription_overview, and that it requires a one-time token from prepare_mutation. This gives clear prerequisites and a safety rule, leaving no inference needed.

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