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, openWorld), so the description earns credit for going beyond them: it discloses the required auth scope (`assets:read`) and describes the ACL's shape, including the enum of default decisions and nickname resolution. It does not cover error behavior or rate limits, but for a read-only tool this is solid.

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?

Three tight, front-loaded parts: what is returned, how the ACL is composed, and the auth requirement. No filler sentences, and the most important information leads.

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 explains what comes back (default decision values, per-user override rules, nickname resolution) and states the auth requirement; parameters are fully handled by the schema. Only the absence of any routing to the sibling write tool keeps it from a 5.

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 description coverage is 100% – both `url` (format, example, no-query-params constraint) and `account` (label semantics) are fully documented in the schema. The description adds no parameter-level detail, so the baseline of 3 applies.

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 gives a specific verb and resource ('Returns the Access Control List currently applied to a fal CDN file') and even characterizes the return structure (default decision plus per-user overrides). It is clearly distinguishable from set_storage_file_acl, but it never explicitly names that sibling, so differentiation is by inference only.

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 implied – you call this to inspect a file's ACL – but there is no explicit when-to-use guidance, no conditions, and no reference to the write counterpart set_storage_file_acl or to sign_storage_file_url. Adequate but with clear gaps.

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