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

Annotations only supply the generic flag set; the description adds real substance: what Onplana persists (URL + metadata only), what is explicitly not done (no download/copy in V1, framed as a security stance), and the auth requirement. This is well beyond annotation coverage.

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?

Front-loaded with the operation and the LINK semantics, then the no-copy constraint and auth note. Four tight sentences with little waste, though the parenthetical '(security stance)' and repeated 'no download/copy' framing is mildly redundant.

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?

Behavior, storage model, and prerequisites are complete for a mutation tool, and there is no output schema to explain. The remaining gap is purely parameter-level: four undocumented identifiers with no schema descriptions.

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 0% and the description documents none of the four identifiers. It hints that siteId refers to a SharePoint site, but libraryId, driveItemId, and projectId are left entirely for the agent to infer, and no format or ID-source guidance is 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 (attach), resource (SharePoint document), and destination (Onplana project workspace), and pins the exact mechanism (LINK reference, externalProvider=SHAREPOINT). This cleanly separates it from upload-style siblings and from generic attach_link.

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 prerequisite ('caller must have read access to the SharePoint site') and the V1 security stance that no file is copied, which constrains when this is the right choice. It stops short of explicitly naming alternatives like attach_link or upload_library_document and the condition that selects them.

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