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

Annotations already cover read-only, non-destructive, closed-world, so the bar is lower. The description adds genuinely non-obvious behavior: results are credential-scoped, and the row flagged current reflects the call's existing scoping, with no current row when reads span the whole account.

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?

Dense but front-loaded: purpose first, domain definition second, scoping mechanics last. The final sentence about the current row is slightly convoluted, but every sentence carries real information and nothing is padding.

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?

There is no output schema, so the description must carry return-shape burden; it covers the id and the current flag but never states the other likely fields (e.g. name/slug/status). Otherwise it is complete enough for a zero-parameter discovery call.

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?

This tool has zero parameters, so the baseline is 4. The description still adds value by explaining how the ids it returns are consumed by other tools (project argument, x-fnlowl-project header, FNLOWL_PROJECT).

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 and resource ('Lists the projects') plus scope ('this credential can act on'), and then defines what a project is in this domain. An agent can immediately distinguish it from create_project and from the other list_* tools.

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?

Explains the practical follow-on: take an id and pass it as the project argument, header, or env var, and note that with neither, tools read across the whole account. That is strong when-to-use context, though it never explicitly says 'call this first to discover valid project ids' or when not to call it.

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