post--v3-domains-domain_name-messages-storage_key

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

With no annotations provided, the description carries full burden but offers minimal behavioral insight. 'Resend' implies a mutation/write operation, but it doesn't disclose authentication requirements, rate limits, whether the original message is preserved, what happens on failure, or the expected response format. This leaves critical behavioral aspects undocumented.

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 extremely concise with just two words, front-loading the core action. There's no wasted language or redundancy, making it efficient for quick scanning.

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 mutation tool with 3 parameters, no annotations, no output schema, and low schema description coverage, the description is inadequate. It doesn't explain what 'resend' entails operationally, how parameters interact, what 'storage_key' refers to, or what the tool returns. More context is needed for safe and effective use.

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 33% (only 'to' parameter has a description). The tool description adds no parameter information beyond the schema. Since schema coverage is low (<50%), the description fails to compensate for undocumented parameters like 'domain_name' and 'storage_key', leaving their purpose unclear. Baseline 3 applies as schema does some work but gaps remain.

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 'Resend an email' clearly states the action (resend) and resource (email), but it's vague about scope and context. It doesn't specify whether this resends from storage or recreates a message, and doesn't distinguish from sibling tools like 'post--v3-domain_name-messages' which appears to create new messages.

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?

No guidance is provided about when to use this tool versus alternatives. The description doesn't mention prerequisites (like needing a stored message), exclusions, or compare it to similar tools such as 'post--v3-domain_name-messages' for sending new emails.

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