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

Annotations already cover the safe, idempotent, read-only profile, so the bar is lower; the description still adds real value by disclosing the optimistic-concurrency contract — the returned etag must be echoed as expected_etag or the write is refused if the file changed. It omits failure modes such as a missing file or binary/large-file handling.

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 tight sentences with no filler, and the returned value is stated first with the etag workflow immediately after. The opening fragment is not a full clause, slightly weakening front-loading, but nothing is wasted.

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 two-parameter read tool with full schema coverage, an output schema and complete annotations, the description supplies the one thing structured fields cannot: why the etag matters and how it prevents lost updates. Nothing essential to calling it correctly 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 both parameters (slug, filename) are documented with examples, so the schema does the work and baseline 3 applies. The description adds no syntax or constraint detail for slug/filename; its only parameter-adjacent content concerns expected_etag on a different tool.

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 names the resource precisely ('one file's content and etag') and pairs it with the write tool that consumes the etag, so an agent can tell it reads a single project file rather than listing or writing. It never states an explicit verb ('returns'/'reads'), so it stops just short of a 5.

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?

It explains the downstream use of the etag on colony_write_project_file, which is useful workflow guidance, but it never says when to reach for this tool versus colony_get_project or colony_vault_get_file, or what preconditions exist (e.g. file must exist). Usage is implied by the resource name rather than stated.

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