update_result

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

Annotations only declare readOnlyHint=true, so the description carries real weight and does: a 30-minute blocking wait, a possible repeat still_running result, the meaning of never_started=true, and the escalation path when state is unknown. It does not contradict readOnlyHint since the tool observes rather than mutates, though the long-blocking nature could be signaled more prominently.

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-loads the action and scopes it immediately, then packs the failure semantics into short clauses. The nested parenthetical about waiting and the cross-reference to apply_updates' result form make it dense, but no sentence is wasted.

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 long-poll tool with no output schema, it covers timeout, repeat-result behavior, the never_started case, and the blocked/human-check outcome. The return shape is delegated to apply_updates' documentation rather than described here, which is the only meaningful gap.

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 100% with a well-described vmid, so the baseline is 3. The description adds genuine meaning beyond the schema by tying vmid to the specific prior apply_updates call, which the schema does not convey.

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 — wait for a still_running update from apply_updates and return its result — and explicitly names the sibling that produces the state it consumes. An agent can distinguish this from apply_updates without opening either 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?

Gives an explicit precondition (only after apply_updates reported still_running), an explicit argument source (pass the vmid of that call), and an explicit do-not-retry rule when pvewarden cannot determine the outcome. The alternative and its selection condition are named.

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