list_sinks

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

Annotations already indicate read-only, non-destructive, and idempotent behavior. The description adds behavioral context by specifying exactly what information is returned (license, optional extra, status, capabilities, read-serving sink) and explicitly notes that it 'Reads no filings,' which clarifies it doesn't access underlying data. This goes beyond the annotation basics.

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 two short sentences, front-loaded with the usage trigger. Every word provides necessary information—no filler. The list of returned fields is compact yet complete for the tool's purpose.

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?

Given the tool has no parameters and an output schema is present, the description sufficiently explains the purpose and return content. The note that it doesn't read filings is a valuable clarifier, ensuring the agent doesn't confuse it with data access tools. No critical gaps remain.

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 parameter semantics are trivially satisfied. The description adds value by detailing what the response will contain, which helps the agent set expectations even though no input is needed.

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 lists configured databases and their capabilities, with a specific verb ('Returns') and resource ('sink id'). It distinguishes itself from siblings like verify_sinks, as it focuses on listing configuration and capabilities rather than verifying functionality.

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?

Explicitly states the trigger condition: 'when the user asks which databases are configured or their capabilities.' While it doesn't name alternatives, this is unambiguous for this tool's use case, and sibling differentiation is implied by the distinct purpose.

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