email_savings_card

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

Beyond the annotations, the description discloses meaningful behavior: the consent requirement, that the message contains only the card, that FineRx does not store the address, the masked return format, and the proper error-handling response. This gives the agent a clear mental model of side effects and privacy implications.

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, front-loaded with the core purpose, and organized into clear short directives covering prerequisites, behavior, return values, and prohibited actions. Every sentence adds operational value without unnecessary elaboration.

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 combination of the detailed description, annotations, and output schema fully equips an agent to invoke the tool safely and correctly. It covers consent, address handling, error response, and fallback behavior, leaving little unstated. The locale parameter is the only minor gap, but it has a default and is not essential for the core call path.

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?

The input schema has 0% description coverage, but the tool description compensates well for email and consent by explaining that consent must be explicitly obtained and set to true. It does not explain the 'locale' parameter, which remains ambiguous, so it is not a perfect compensation.

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 first sentence states a specific action ('Email the free FineRx discount card') and the exact target ('to an address the person gave you'). This clearly distinguishes it from sibling tools like get_savings_card, which retrieves rather than sends.

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 explicitly states when to use the tool ('ONLY after the person has given an email address AND confirmed they want the card sent there') and includes explicit prohibitions ('Do not call without an explicit yes', 'do not retry a refusal'). It also offers fallback alternatives on error: offer the image or link instead.

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