hmc_add_vnic

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

No annotations are provided, so the description carries full burden. It discloses that the tool modifies LPAR configuration, runs a specific HMC CLI command, performs UUID resolution with fallback, returns raw command output, and raises HMCCLIError on failure. It also issues a warning to confirm parameters. This is comprehensive and transparent.

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 well-structured with a clear opening, command details, scope boundary, return value, warning, and error raising. It uses formatting (bold, inline code) effectively and every sentence adds value without unnecessary verbosity.

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 the tool's complexity (6 params, no annotations, no schema coverage), the description covers the key aspects: what the command does, how UUID resolution works, scope limitations, return value, warning, error handling, and prerequisites. It could be more complete with per-parameter examples or allowed values, but overall it provides enough context for an agent to invoke the tool correctly.

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 lists the supported parameters (capacity, vswitch_name, port_vlan_id, backing_devices) and clarifies backing_devices is an opaque string, plus explains that system/lpar may be names or UUIDs. However, it does not define units for capacity, valid ranges for port_vlan_id, or the meaning of vswitch_name beyond its name, leaving some param semantics unclear.

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 'Add a vNIC (SR-IOV-backed Virtual NIC) to an LPAR via the HMC CLI' which clearly states a specific action, target resource, and technology. It distinguishes itself from sibling tools like hmc_add_vscsi_adapter and hmc_add_vfc_adapter by focusing on SR-IOV vNIC creation.

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 provides clear context for when to use the tool: it adds an SR-IOV vNIC and notes a prerequisite (underlying adapter must be in SR-IOV mode, see hmc_set_sriov_adapter_mode). It also states what is out of scope for v1 (complex backing-device topology). However, it does not explicitly compare against alternative adapter-creation tools or state 'use this instead of...'.

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