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

Annotations already declare readOnlyHint=true, destructiveHint=false, openWorldHint=false, so safety is covered. The description adds that this becomes the pipeline's data-reader source, which is useful, but it does not say whether loading changes editor/open-record state, what happens to a previously loaded record, or any failure modes for a missing/ambiguous document name.

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?

A single front-loaded sentence with an em-dash clarifier; no repetition or filler. The phrase "instead of whatever happens to be open in the editor" is colloquial but earns its place as the differentiator.

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?

An output schema exists, so return values need no explanation, and all three parameters are fully documented in the schema. For a read-only loader the description is largely sufficient, with only the side-effect question (does it alter open-record state?) left unaddressed.

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%, including the document parameter's "id, or its exact name (`list_library` lists them)" and the _subject/_files structures. The description adds only that the document is "chosen," which is already implied; baseline 3 applies when the schema carries parameter meaning.

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: "Read a CHOSEN project document as a record," and adds that it is the pipeline's data-reader source. It implicitly distinguishes itself from the open-editor path, though it never names the sibling (get_open_record) explicitly.

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?

Gives a clear usage condition: use it to run on a specific file "instead of whatever happens to be open in the editor." That is a real when-to-use rule, but there are no explicit exclusions and no named alternative tool, so the agent must infer the counterpart from phrasing.

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