ghl_conversation_add_message_attachments

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

Disclosed that attachments are replaced (not appended), max 5 URLs, and the operation is for specific message types. Annotations already indicate readOnlyHint=false and destructiveHint=false, and the description adds contextual constraints. No contradiction.

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 concise, front-loaded with the core action, and efficiently covers purpose, constraints, and related endpoints in a few sentences without 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 simple tool with 2 parameters and no output schema, the description covers the operation, constraints, supported message types, and OAuth scopes. Missing return value details but acceptable given no output schema.

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% with clear descriptions for both parameters. The description repeats some schema info (e.g., max 5 URLs) and adds the upload distinction, but adds limited new semantic meaning beyond what the schema already provides.

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 tool replaces/adds attachment URLs on an existing message, using specific verbs and resource. It distinguishes from the file-binary upload endpoint, making the 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?

The description explicitly contrasts with the upload tool and specifies supported message types (TYPE_CUSTOM_CALL, TYPE_CALL with subType EXTERNAL_CALL). However, it does not differentiate from other conversation sibling tools like add inbound/outbound message, which could lead to confusion about when to use this vs those.

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