faf_trust

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds meaningful context beyond that: it shells out to faf-cli, checks well-formedness/parsing, and returns an "always-33 score," which is non-obvious behavior an agent could not derive from the schema.

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 tightly written sentences, front-loaded with the action and followed by the rationale. Every clause earns its place and there is no 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?

For a zero-required-param, read-only validator with no output schema, the description covers what it does and what it returns (a score) well enough to call correctly. It could say more about failure output or how errors surface, but nothing essential is missing.

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 single optional path parameter is fully documented in the schema itself (directory to check, defaults to cwd). The description adds no parameter detail, so the baseline 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?

Names a specific verb and resource: validates a project.faf via faf-cli and reports its score. The intent (confirm the context file parses cleanly) is concrete. It does not explicitly differentiate from the sibling faf_score, which also concerns scoring, so an agent must infer the split.

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 pre-flight trust check: never build on a broken context layer" implies the usage window (before an agent grounds on the file), which is real guidance. However, it never names an alternative or states when NOT to use it, and with faf_score and faf_init present as siblings, the routing choice is left implicit.

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