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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so 'read-only' is redundant, but the description adds genuinely new behavior: 'not metered', the bytes_available=false case for a portable Standard Statement admitted without its original, and the fact that chart/declaration rows hold the exact sealed register. That is meaningful disclosure of edge-case row semantics beyond the annotations.

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?

The scope statement is front-loaded and the download routing is placed last, which is the right ordering. It is dense with domain jargon ('transfer tier's retained artifacts', 'sealed document register') and runs long, but nearly every sentence carries distinct information.

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 single-parameter read tool with a full output schema and complete annotations, the description covers scope, row contents, the key bytes_available caveat, and the download path. Nothing an agent needs to call or interpret it 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?

There is a single parameter and schema description coverage is 100%, with the schema itself explaining that workspace_tag is the id returned by create_workspace and list_workspaces. The description adds no parameter-level meaning beyond that, so the baseline 3 applies.

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 documents admitted to a workspace') and immediately scopes it against a sibling concept ('not the transfer tier's retained artifacts'), which separates it from list_transfer_sessions. It also enumerates what a row contains, so an agent knows exactly what it gets back.

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?

Names the follow-on tool for the common next step ('Retained bytes download via create_download_sessions with source_document_id (or chart_id / declaration_id)'), which is real routing guidance. It also implicitly excludes the transfer-tier listing, but never states an explicit when-not-to-use condition or prerequisite beyond an active workspace.

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