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

With no annotations provided, the description carries the full behavioral burden and does so thoroughly. It discloses id immutability tied to the crontab symbol, partial-update semantics, persistence of history and commands when deactivating, the query-cost implication, the critical caveat that the device keeps sending, and that the response is the authoritative current collection.

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 description is front-loaded with its purpose, and each later sentence adds a distinct behavioral or response fact rather than restating the schema. It is longer and more vivid than strictly necessary, especially the crontab rationale, but the length is justified because there are no annotations and the tool has nontrivial side effects.

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?

Given no annotations and no output schema, the description covers the essential execution model: what changes, what persists, what deactivation means and does not mean, and that the returned collection should be used as the source of truth. Parameter format constraints are already in the schema, so no significant gap remains.

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?

The input schema already documents all four parameters with 100% coverage, so the baseline is 3. The description adds meaningful semantics beyond the schema: partial-update behavior for omitted fields, why the id is immutable, and what ativa:false and ativa:true actually do to fleet reading, query cost, and device behavior.

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?

The description opens with concrete operations ('Renames one measurement, or stops and resumes reading it') tied to the collection resource. It distinguishes this from create/delete/list siblings by naming the exact mutation surface and adding the invariant that the id never changes.

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 description gives clear context for when to use the tool: partial updates, renaming, and toggling active state. It also warns that ativa:false does not silence the machine and that the cron line must be removed instead, which is an explicit exclusion. It does not name sibling tools as alternatives, but the context is clear and the guidance is not misleading.

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