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

Annotations already establish this as a safe, idempotent read, and the description adds substantial operational detail beyond them: a 5-file cap at 10 MB each, iteration in field and cell order, a text budget with `more` counting the remainder, and the `unreadable` bucket with reasons and Drive links. It also discloses that other members' Drive files and images are deliberately excluded from reading.

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 verb and scope, then constraints, then edge-case handling — a sensible order. It is dense and backtick-heavy in the middle sentence, but every clause (caps, ordering, formats, `more`, `unreadable`) carries information an agent needs.

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 an output schema present, return-value documentation is not required, yet the description still explains the two response-relevant concepts an agent must act on (`more` and `unreadable`). Combined with format support and size caps, nothing needed to call this correctly 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?

Schema coverage is 67%, and `attribute` is already documented in the schema; the description reinforces it as the single-field selector, which is useful but largely duplicative. `sheetId` has no schema description and the description does not explain it either, leaving the weakest-covered parameter unaddressed. Baseline 3 is appropriate given the schema does most of the work.

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?

Opens with a specific verb and scope: 'Read the text of the files on one row', and enumerates the two sources it covers (uploads in File List fields, and user-linked Google Drive files). This is clearly distinguishable from sibling tools like file.confirm_upload, sheet.read, or page.read.

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 concrete routing guidance: pass `attribute` to narrow to one field, and send audio uploads to `audio.transcribe` instead. It also instructs what to do with `unreadable` entries (tell the user, never guess). It does not, however, say when to prefer this over reading field values via sheet.read or peek.read, so the alternative-selection guidance is incomplete rather than absent.

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