Assign DataLens licences

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

Annotations already carry the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false), so the bar is low; the description still adds genuine context by flagging the operation as billable ('a licence is a seat DataLens bills for') and stating it returns the licences granted. It stops short of covering revocability or repeat-call behavior.

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?

The first sentence is tight and front-loaded, but the trailing fragment 'Written from the DataLens document and never called: not measured.' is confusing meta-commentary that does not help an agent invoke the tool and arguably does not earn its place.

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 single-parameter write tool with no output schema, the description covers purpose, cost, and consent, which is reasonable. It omits auth/permission requirements and what happens to already-licensed users (idempotentHint is false), leaving meaningful gaps for a billing-relevant mutation.

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?

Only one parameter exists and schema description coverage is 100%, so the schema fully documents user_ids. The description's 'each of these users' merely echoes the array semantics without adding format or constraint detail; baseline 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+resource ('give each of these users a licence') and even describes the return ('return the licences given'). However, it never distinguishes itself from licensing siblings such as datalens_licensing_licenses_list or datalens_licensing_limit_set, so the agent gets no explicit routing help.

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 caution 'ask the person before calling' gives a real prerequisite (consent/cost), which is implied when-to-use guidance. But there is no stated alternative, no condition for choosing this over listing licences or setting the limit, and no explicit exclusion, so usage stays at a minimum-viable level.

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