add_partitions

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

With no annotations, the description carries the full burden and does it well: it discloses the confirm gate, that no change happens unless confirmed, that the batch is non-atomic with no rollback after partial success, that keyed-message ordering can break, and that Kafka ALTER permission is required. It also states duplicate topic names are refused before anything changes.

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?

Purpose and scale are front-loaded and every paragraph carries real information about risk or gating. Phrasing is slightly awkward ('increase the partition count of 1 to 1000 topics in one call through items') and the trailing note on acknowledge_key_ordering reads as an afterthought rather than integrated with the confirm discussion.

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 high-risk mutation with no annotations, the description covers permission needs, gating, atomicity limits, and ordering hazards. An output schema exists, so the brief note about per-item results carrying index with result or error is sufficient rather than a gap.

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% and the per-item fields are already well documented, so the schema does the heavy lifting. The description reinforces batch semantics ('one confirm covers the whole batch', 'results follow items order, each carrying index with result or error') but adds little that the schema does not already say.

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?

States a specific verb and resource ('increase the partition count') plus an explicit scale ('1 to 1000 topics in one call through items'), and clarifies that a single-topic change is just an items array of length one. Combined with the 'Kafka cannot remove partitions' constraint, an agent can tell this is the in-place resize operation, distinct from siblings like create_topic or alter_topic_config.

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?

Gives clear operational context: batch via items, a dry-run default when confirm is absent, and the requirement to set acknowledge_key_ordering for keyed topics. It never names a sibling alternative (e.g. create_topic for new topics), so the exclusion side of the guidance is missing.

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