Update recurring job

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

With no annotations, the description carries full weight and excels: it discloses the read-merge-write client-side behavior versus the server's full-replace PUT semantics, flags 'Destructive,' and warns that lowering `retain` can prune existing snapshots/backups beyond the new limit — a non-obvious side effect an agent would never infer from the schema.

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, then merge semantics, destructive flag, and authorization guard in order of decreasing importance. Every sentence earns its place; the docs link is a useful tail rather than a distraction.

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 destructive mutation with 8 params, no annotations, and no output schema, this is nearly complete: safety profile, merge semantics, destructive side effects, and a documentation link are all present. It falls short of 5 only by not describing the return value or the outcome when the named job does not exist.

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 0%, so the description must compensate. It adds real meaning for `retain` (lowering it can prune snapshots/backups) and for all omitted fields (they stay unchanged), but it leaves cron format, task values, groups, labels, parameters, and concurrency unexplained; the docs link is the only pointer for those.

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 ('Update an existing Longhorn recurring job') where 'existing' distinguishes it from recurringjob_create. The scope is unambiguous and easily told apart from the sibling list/get/delete variants without opening the schema.

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?

Provides an explicit authorization gate — 'Do not call this unless the user has explicitly authorized it in this conversation — never proactively, speculatively, or as a side effect of another task' — which is strong when/when-not guidance. However, it never names sibling alternatives such as recurringjob_create for new jobs, so routing between related tools is left implicit.

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