Acquire a VM

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

With all annotations false, the description carries the full behavioral burden and does so richly: it discloses the ownership heartbeat, that nothing is extracted automatically, that env is never baked into images, that vnc only prepares console-sharing and never opens a viewer, and that a failed step keeps the VM for repair rather than replaying uncertain input.

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 dense but mostly front-loaded, leading with the core action and required parameters. The final lifecycle sentence packs many directives and there is slight redundancy between 'One task per enclosure' and 'call this once per task,' so it is not maximally tight.

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 7-parameter lifecycle tool with no output schema and unhelpful annotations, the description gives the agent everything needed to call correctly: prerequisites, optional-parameter semantics, a one-call-per-task constraint, next steps, and failure behavior. The lack of an explicit return-value description is mitigated by the stated handoff to relay_stage/relay_run.

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 only 57%, but the description compensates by explaining task as a short slug, image as a key from relay_probe/relay_search, extractions as pre-declared outputs ([] allowed), ttlHours default 4, env as a credential pack, fullWorkspace as opt-in, and vnc's exact console-sharing semantics.

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 opening sentence names a specific action and resource: 'Acquire one fresh VM for this task and start its ownership heartbeat.' This clearly positions it as the acquisition step and separates it from image-lookup tools like relay_probe/relay_search and later stage/run tools.

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?

It gives explicit preconditions ('Requires task, image, extractions') and lifecycle direction ('Continue with relay_stage, relay_run ... relay_finish or relay_release'), plus an exclusion: 'call this once per task, not again for another task.' It does not name an alternative tool for the same purpose, but the pipeline context makes when-to-use clear.

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