get_messages

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

With no annotations provided, the description carries full burden. It discloses that pagination is supported and no API key is required (addressing authentication needs), which are valuable behavioral traits. However, it doesn't mention rate limits, error conditions, what happens with invalid parameters, or the format/structure of returned messages. For a read operation with 5 parameters, more behavioral context would be helpful.

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 sentences. The first sentence states the core purpose and key capability (pagination). The second sentence provides important authentication context. Every word earns its place with zero waste or 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 read operation with 5 parameters and no output schema, the description is minimally complete. It covers the basic purpose and mentions pagination and authentication, but doesn't describe the return format, error handling, or limitations. With no annotations and no output schema, more context about what the tool returns would be valuable for an agent to use it effectively.

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 100%, so all parameters are well-documented in the schema itself. The description adds marginal value by implying that 'listingId' is central (since it's mentioned in the description text) and that pagination involves 'cursor' and 'limit', but doesn't provide additional semantics beyond what's in the schema. Baseline 3 is appropriate when schema does heavy lifting.

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 verb 'Get' and resource 'messages for a listing' with the additional capability 'with pagination support'. It distinguishes from siblings like 'send_message' (which creates messages) and 'get_listing' (which retrieves listing details rather than messages). However, it doesn't explicitly differentiate from other potential message-related tools that might exist in other contexts.

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 usage context by mentioning 'for a listing' and 'pagination support', suggesting this is for retrieving message history rather than sending. It also states 'No API key required', which provides some authentication context. However, it doesn't explicitly say when to use this versus alternatives like filtering messages by other criteria not supported by parameters, nor does it mention prerequisites beyond the required listingId.

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