list_vendors

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

With no annotations provided, the description carries the full burden of disclosing behavior. It clearly states the action ('list') and the return format (IDs, names, profiles), implying a read-only operation. It does not describe any side effects, permissions, or pagination, but given the simplicity of the tool, this is reasonably transparent. The description adds value beyond the name by specifying the output structure.

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 exactly two sentences: the first states the purpose, the second states the return value. There is no redundant information, and it is front-loaded with the primary action. Every word earns its place, making it highly efficient and 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?

For a simple list tool with no parameters and no output schema, this description is complete. It tells the agent exactly what will happen ('list all') and what to expect in the response (IDs, names, profiles). There are no hidden behaviors or missing prerequisites. The tool's low complexity does not demand additional explanation.

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?

The tool has zero parameters, so the baseline of 4 applies. The description adds no parameter-specific information because none exists, but it does clarify what the tool returns, which is useful for an agent. Since the schema is empty, the description's mention of the return fields is the only semantic guidance available.

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's function with a specific verb ('List') and resource ('registered vendors/counterparties'), plus scope ('all' and 'in the organization'). It immediately distinguishes itself from sibling mutation tools like create_vendor and delete_vendor, as well as other list tools by explicitly naming the resource type.

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 provides clear context on what the tool does—listing all registered vendors—and implicitly indicates when to use it (when needing an overview of vendors). However, it does not explicitly mention when not to use it or alternative tools, such as using create_vendor to add a vendor or delete_vendor to remove one. This clear context without exclusions aligns with a 4.

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