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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered by structured data. The description adds nothing beyond that - no note on error/not-found behavior, scoping, or whether the returned document includes linked folders or file metadata.

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 short sentence with the resource and lookup key front-loaded and zero filler. It is efficient, though its brevity is closer to under-specification than to well-packed density.

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 one-parameter read tool with no output schema, the agent knows how to invoke it but not what a document record contains or how a missing ID is reported. Annotations cover the safety side, so the gap is moderate rather than severe.

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?

There is a single parameter and schema description coverage is 100% ('Project document ID', uuid format), so the schema already carries the semantics. 'By ID' in the description restates rather than enriches the schema, which merits the baseline 3.

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 ('Get a single project document by ID'), which clearly separates it from list_project_documents and update/delete_project_document. It stops short of naming a sibling explicitly, but the 'single ... by ID' scoping makes the intent unambiguous.

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?

Usage is only implied: 'by ID' tells the agent this is the single-record retrieval path as opposed to the list_* variant. There is no explicit when-to-use, no mention of what happens if the document does not exist, and no routing guidance among the many get_* siblings.

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