send_card

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

With no annotations provided, the description carries the full burden and does disclose meaningful behavioral traits: the free-tier hard cap, the restricted relationship values, and the special condition for fact_confirmed. It stops short of explaining side effects such as cost beyond the free tier, delivery behavior, or error handling when the cap is exceeded, but the stated constraints are valuable and non-obvious.

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 every sentence adds information. It front-loads the core purpose, then gives prerequisite and constraint details in tight, scannable sentences. The parameter-specific notes are clearly separated with 'relationship:' and 'fact_confirmed:' labels, making the structure easy to parse.

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?

Given the tool has 10 parameters, no annotations, no output schema, and 0% schema coverage, the description is reasonably complete. It covers the main preconditions and constraints needed to invoke the tool correctly. A few gaps remain, such as the exact meaning of 'plain register' and any guidance on what occasion should be, but the core usage rules are present and actionable.

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 0%, so the description must compensate. It adds real meaning to parameters by specifying that all IDs (template_id, phrase_ids, signoff_id, offer_id, holiday_id) must come from catalog tools, enumerating the two valid values for relationship, and giving a rule for fact_confirmed. It does not explicitly explain sender_name, recipient_email, occasion, or holiday_id, but these are fairly self-explanatory and/or covered by the schema defaults.

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 the specific action 'Send a Dear Human card', naming a clear verb and resource. It also implicitly distinguishes this tool from the sibling getter tools ('get_card_templates', 'get_phrases', 'get_offers', 'get_todays_holidays') by being the only send action in the group.

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 gives explicit context on when to use this tool: 'All IDs must come from the catalog tools' tells the agent to first call the getter siblings to obtain valid IDs. It also provides a hard cap ('First 5 cards per sender are free') and a validation rule for 'relationship'. It does not explicitly name alternative tools or state 'when not to use', but the sibling names and the verb 'send' make the selection clear.

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