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

With no annotations, the description carries the full burden and does it well: it discloses partial-update semantics (only cells in `set` change, other cells' edits are preserved), null-clears-cell behavior, atomic all-or-nothing execution, and a 500-per-call rate limit. These are exactly the behavioral traits an agent needs before mutating data.

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 core action and the input shape, then the important behavioral guarantees. Every sentence carries information—partial-update preservation, null handling, atomicity, and the cap—with no filler.

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 mutation tool with no annotations and no output schema, the description covers the critical semantics (atomicity, partial update, null, limit). The main gap is the absence of any statement about return values or error behavior on a failed batch, but the core calling knowledge is complete.

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 the description compensates well: it spells out the `updates` shape as `[{ id, set: { "<column name>": value } }]`, explains that `set` keys are column names, and defines null semantics. It adds meaning beyond the schema, though it says nothing extra about the `table`/`workspace` params beyond what the schema already documents.

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 with scope: 'Change cells of existing rows by id'. It clarifies it operates on existing rows (distinguishing it from add_rows) and points to query_rows for ids, though it never names upsert_rows as the contrasting sibling.

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?

Prerequisite guidance is present ('ids from query_rows'), which tells the agent where to source input, but there is no explicit when-to-use vs. when-not or comparison against alternatives like upsert_rows or delete_rows. Usage is implied rather than prescribed.

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