send_email_with_template

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

No annotations are provided, so the description carries the burden. It does disclose one important behavior: direct fields (e.g., subject) override rendered ones. However, it does not mention failure modes, authentication requirements, or what the return value is, leaving the agent partially uninformed about side effects and outcomes.

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?

Two concise sentences. The first states the core purpose and mechanism (render + send), the second adds a critical precedence rule. No filler or redundancy; information density is high.

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?

With no output schema and no annotations, the description should explain what the caller receives (e.g., message ID, success flag) and any prerequisites or side effects. It does neither. While parameter semantics are handled by the schema, the tool's return behavior and error conditions are completely undocumented, making it incomplete for a 10-parameter tool.

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 the baseline is 3. The description adds meaningful context beyond the schema by explaining that template_model contains Mustache-style variables and that direct field values override rendered output. This helps the agent understand how parameters interact, justifying a score above baseline.

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 names a specific action (render a stored template and send it) with a clear resource (CamelMailer template) and distinguishes itself from siblings like render_template (which only renders) and send_email (which likely sends without template rendering). The verb 'render' + 'send' is concrete and 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?

The description implies this tool is for sending templated emails but does not explicitly state when to use it over send_email or render_template. There is no mention of alternatives or exclusions, so guidance is only implicit from the wording and tool name.

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