list_capi_functions

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

With no annotations provided, the description carries the burden of behavioral disclosure. It reveals that the tool reads from a 'committed ABI snapshot' (implying possible staleness) and returns a well-defined set of signature components. It does not explicitly state read-only, but the read-only nature is strongly implied by 'Search' and 'Returns'.

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: two sentences that front-load the purpose and then provide usage guidance. Every word adds value without any redundancy or filler.

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?

The tool is simple (two optional params, no output schema), and the description covers the core purpose, usage context, and return content. It could be slightly more complete by showing an example output shape, but it is adequate for an agent to invoke the tool correctly.

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 provides 100% coverage for both parameters (limit and filter) with clear descriptions. The tool description adds no additional parameter semantics beyond what the schema already offers, so the baseline score of 3 is appropriate.

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: searching the FLOX C-API surface and returning name, return type, and parameter types for every exported flox_* function. It uses a specific verb ('Search') and resource ('C-API surface'), and distinguishes from siblings like lookup_symbol by focusing on the complete list of exported symbols.

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 states when to use the tool: when the user is writing FFI code (Codon, QuickJS, Rust cgo, ctypes) or asks 'what C symbols can I call'. While it does not mention specific alternatives or exclusions, the given context is clear enough to guide selection among sibling tools.

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