Change the roles on a DataLens workbook

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

Annotations already declare this is a non-read-only, non-idempotent, non-destructive write. The description adds a genuinely useful behavioral fact beyond them: it is a merge-style delta operation where unspecified roles are preserved. It still omits permission requirements and what happens when an ADD targets an already-present binding (notable given idempotentHint=false).

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?

A single sentence of two tight clauses, with the core action front-loaded and the merge semantics appended. No filler, no restatement of the title.

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 two-parameter mutation with full schema coverage and annotations carrying the read/write and idempotency profile, the description supplies the one thing the structured fields don't: the delta/merge semantics. It could still mention required permissions or error behavior on conflicting bindings, but nothing essential for correct invocation 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 description coverage is 100%, so workbook_id and the deltas structure (action, accessBinding.roleId, subject.id/type) are already documented in the schema. The description adds no syntax or format detail beyond that, so the baseline of 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 phrase ("Give or take away roles") and the resource ("a workbook"), so an agent immediately knows this mutates workbook access bindings. It does not name or contrast itself with the near-identical siblings datalens_collections_access_bindings_update or datalens_sharedentries_access_bindings_update, leaving scope differentiation to the tool name.

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?

The clause "the roles not named stay as they are" implies this is a partial/delta update, which hints at when to use it (incremental changes rather than full replacement). However, no alternatives are named and there is no guidance on when to add vs. remove or when to use the sibling bindings_list tool instead.

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