add_iscsi_target

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

Annotations already mark this as non-readOnly, non-idempotent, and non-destructive; the description adds rich context beyond them: what the preview returns (blast radius contents), that nothing changes without confirm, refusal conditions, and that a duplicate address:port yields action "noop".

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 core action in the first sentence, then the safety/gating rules. Slightly dense but nearly every clause carries actionable information about preview behavior or refusal conditions; no filler.

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 6-parameter mutation tool with no output schema, the description covers the mutation semantics, preview/apply gating, failure modes, and the side-effect rescan. Coverage is strong, though the returned dict's shape is only named (blast_radius, action) rather than detailed.

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% so parameters are already documented, but the description adds meaningful semantics for the gating flag (confirm=True applies, otherwise preview) and reinforces the deprecated dry_run alias relationship and the enable_iscsi dependency. This exceeds the baseline 3 without fully restating every field.

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?

Opens with a specific verb and resource: adding an iSCSI send (dynamic discovery) target to an ESXi host's software iSCSI adapter, plus the automatic HBA/VMFS rescan. It is clearly distinguishable from siblings like remove_iscsi_target, enable_iscsi, and rescan_storage.

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?

Explicitly states the confirm=False preview default and instructs the agent to show the blast radius and not set confirm=True on its own; it also says no separate rescan_storage call is needed and directs to enable_iscsi when software iSCSI is disabled. When-to-use and prerequisites are fully spelled out.

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