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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds genuinely new context beyond that: access depends on the document's type, with bank, statement, load and own-upload permission scopes — a real authorization caveat an agent cannot get from structured fields.

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?

Two short sentences, front-loaded with the core operation before the permission caveat. No filler; the second sentence is slightly compressed ('its type' requires the reader to infer document type) but nothing is wasted.

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, the description should indicate what 'opening' yields (file content, metadata, signed URL, extracted fields). It covers access rules but leaves the return shape and any 'not found / unauthorized' behavior unspecified, so an agent knows when to call it but not what to expect back.

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?

One required parameter with 0% schema description coverage, and the description never mentions 'document_id' or that it is a UUID. 'Previously found' does give the practical hint that the ID originates from a prior search result, which is meaningful, but the description does not compensate for the total lack of schema documentation.

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 ('Open') and resource ('one previously found workspace document'), making clear it is a single-document fetch rather than a list. It implicitly contrasts with search_documents via 'previously found', but never names the sibling, so the differentiation is inferential rather than explicit.

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?

'Previously found' hints that this is a second-step call after a search, which is useful implied ordering. However, no alternative is named, no exclusion is stated (e.g., 'use search_documents to locate an ID first'), and no precondition is spelled out.

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