About .faf

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

Annotations already declare readOnlyHint and idempotentHint, so safety is covered. The description adds useful behavioral context: it reads nothing and writes nothing, returns plain text, and includes the server version. This is more than the annotations provide and is clearly stated.

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 sentences, front-loaded with the core purpose. It is tight but slightly packs three ideas (definition, output, usage) into the first sentence, which is still efficient. Minor room to split, but no wasted words.

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 no-parameter, no-output-schema tool, the description covers what it does, what it returns, and when to use it. With annotations covering read-only behavior, no further context is required.

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?

Zero parameters, so baseline is 4. The description correctly implies no input, and the schema confirms an empty object. No further parameter detail is needed or given.

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 ('Explain') and resource ('.faf format'), then adds concrete scope: what it is, how this server uses it, and that it returns a plain-text overview with server version. This clearly distinguishes it from siblings like faf_score or faf_init, which perform operations.

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?

Provides explicit when-to-use guidance: 'Use it when someone asks what FAF is.' It doesn't name alternative tools, but none of the siblings serve this explanatory purpose, so implicit exclusivity is reasonable.

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