hcloud_list_addon_instances

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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint. The description adds only the distinction that these are 'installed' add-ons, not available ones, and that they belong to a CCE cluster. It does not disclose pagination, sorting, auth requirements, or return shape, so the extra context is modest.

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 definition is a single front-loaded sentence with zero filler. It states the action and scope immediately and contains no redundant or hedging language.

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 simple two-parameter list operation with full schema coverage and read-only annotations, the description is nearly complete. It could mention pagination or the shape of the listing, but no output schema exists and the tool complexity is low, so the remaining gap is minor.

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 100%, so the schema provides both required parameters. The description adds no meaning beyond that: it does not explain region or cluster_id semantics, and the schema descriptions are minimal ('Region', 'Cluster ID'). The baseline 3 applies when the schema carries the parameter documentation.

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 states a specific verb and resource: 'List installed add-ons in a CCE cluster.' It is clearly distinct from sibling tools about clusters, nodes, or node pools. It stops short of explicitly differentiating from a dedicated add-on listing alternative, which does not exist in the siblings, so a 4 rather than 5.

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?

Usage is only implied by the resource scope: an agent would use this when it needs installed add-ons for a CCE cluster. There is no explicit when-to-use guidance, no exclusions, and no named alternative for related queries such as listing available add-ons.

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