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

The annotations already establish readOnlyHint=true, destructiveHint=false, and a closed-world scope, so safety is covered. Beyond that, the description adds real value by explaining that reference documents additionally return measures, thresholds, and drill paths, which tells the agent what to expect in the payload for each document class.

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?

Three sentences, all front-loaded with the core purpose first and the document-class distinction second. Nothing is redundant, though the final sentence about measures/thresholds/drill paths could be tightened slightly without losing meaning.

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?

With no output schema present, the description carries the burden of describing returns, and it does so at a high level (complete content, plus measures/thresholds/drill paths for reference docs). For a read-only lookup with fully documented parameters and annotations covering the safety profile, this is nearly complete; only the response envelope shape and error behavior for a missing document are unstated.

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%, and the schema itself documents fileId, fileName, datastoreId, and datastoreSlug including examples and the note that fileName accepts a file id. The description restates the file-name-or-id choice but adds no new syntax, precedence, or narrowing semantics beyond what the schema already provides, making the baseline 3 appropriate.

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 opens with a specific verb and resource ('Get the full content of a datastore document') and immediately qualifies the two lookup keys ('by file name or file id'). It also distinguishes itself from related tools by naming where ids come from (datastore_discover, datastore_get_files), so an agent can tell it apart from datastore_get_chunks or datastore_query without opening a schema.

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 gives clear context for use: retrieving the complete content of either a provisioned reference document or a file in the company's own datastores, and it points at the tools that produce the identifiers. It stops short of explicit exclusions (e.g. 'use datastore_get_chunks instead when you only need a passage'), so the alternative-routing guidance is implied rather than stated.

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