Get file ACL

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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), so the description adds genuine value on top: it states the assets:read auth requirement and explains that rule users are returned as nicknames. It does not discuss pagination or rate limits, keeping it at a solid 4 rather than 5.

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?

Front-loaded with the return statement, then a compact explanation of ACL composition, then the auth requirement. Well organized with no filler, though the ACL-structure sentence is slightly more than the minimum needed.

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?

With no output schema, the description usefully describes the returned ACL shape (default decision plus per-user overrides) and the auth prerequisite. Complete enough for the agent to call and interpret the result, though it omits any handling of empty or missing ACLs.

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 coverage is 100% and the schema itself documents both url and account in detail (including format and query-parameter constraint). The description adds no parameter-level meaning, so the baseline 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?

States a specific verb ('Returns') and a precise resource ('the Access Control List currently applied to a fal CDN file'), which an agent can easily tell apart from set_storage_file_acl. It does not explicitly name the write sibling, so it falls just short of the distinguishing-without-schema bar, but the purpose is unambiguous.

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?

Usage is only implied: the agent can infer this is the read path for inspecting ACLs before a set_storage_file_acl call, and the auth prerequisite ('API key must have assets:read') is given. There is no explicit when-to-use, when-not, or named alternative, so guidance is minimal-but-adequate.

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