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

Annotations only declare readOnlyHint=true, yet the description adds substantial behavioral context: it is read-only, Ankra does not upgrade add-ons on its own for advisories and the owner decides, it discloses freshness signals (feed_checked_at, feed_stale), and it warns that an empty result on stale or unread data is not a clean bill of health. This is exactly the extra context the annotation cannot carry.

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-loaded and dense: the first sentence enumerates the returned fields, the second adds the caveats and the read-only/no-auto-upgrade stance. Every element is useful, though the first sentence is long and runs several clauses together, making it slightly heavy to parse.

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?

There is no output schema, so the description carries the full burden of describing returns, and it does so thoroughly (advisory id, severity, summary, link, running release, fixing release, upgrade_chart_version, unjudged add-ons, feed freshness). Combined with the safety caveat, an agent has everything needed to call and interpret it.

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 cluster_id and addon_name are already fully documented in the schema (including the list_clusters discovery hint). The description adds no format or syntax detail beyond that, so the baseline 3 applies.

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 very specific purpose: surfacing installed add-ons whose running version is covered by an upstream security advisory, with a fix available, plus per-add-on fields (advisory id, severity, summary, link, fixing release, upgrade_chart_version). That is far more specific than a name restatement. It does not, however, differentiate itself from close siblings like get_cluster_addon_security or get_security_advisory, so an agent cannot tell which to pick from the description alone.

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 implied by the description's framing (checking add-on advisory exposure), and it does add interpretive guidance: an empty list on stale or unread data is not an all-clear. But there is no explicit when-to-use, when-not-to-use, or named alternative among the many add-on/security siblings.

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