Describe function

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

With no annotations, the description carries the full burden. It explicitly states the tool is read-only and never executes the function, which is a key behavioral disclosure. It also enumerates what data is returned, adding context about the tool's operation. However, it does not discuss error handling, required permissions, or output formatting, so it's good but not exhaustive.

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?

Two short sentences, front-loaded with the main verb and object. Every word earns its place, and the read-only caveat is a single clause. No 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?

Given the tool's simplicity (2 required params, no output schema, no annotations), the description covers all the essential aspects: what data is returned (parameters, return type, SQL definition) and the behavioral guarantee (never executes). It could be more exhaustive about edge cases, but for its complexity, it's sufficient.

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 input schema already contains descriptions for both parameters (schema and function) at 100% coverage. The description does not add any additional meaning about the parameters themselves; it only describes what the tool returns, not how to specify the arguments. Therefore, it sits at the baseline.

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 uses a specific verb 'Get' and clearly identifies the resource ('a function') and the scope of what is returned (parameters, return type, SQL definition). It distinguishes from sibling tools like describe_procedure and list_functions by focusing on the function's metadata and definition, plus adding a read-only note.

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 for when to use the tool: when you need a function's parameters, return type, or SQL body. It also effectively says 'when not' by stating it never executes the function, implying that execution is out of scope. It does not explicitly name alternatives, but the read-only caveat is a usage guideline.

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