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 so well: it discloses irreversibility (Kafka cannot remove partitions), the ordering risk for keyed messages, the confirm gate, batch-level non-atomicity with no rollback, item-ordered results with index, and the required Kafka ALTER permission. This is rich behavioral context an agent could not derive from structured fields alone.

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 is front-loaded and sentences are dense with distinct facts (batch size, irreversibility, confirm gate, non-atomicity, result shape, permission). Minor redundancy in restating the single-topic-as-length-one case, but no filler sentences.

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?

Although an output schema exists and return values need not be described, the definition still explains result ordering and the per-item index/result-or-error shape and covers confirmation, atomicity, permissions, and ordering risk. Nothing an agent needs to invoke it correctly is missing.

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 the baseline is 3, but the description adds batch-level meaning the schema does not convey on its own: results follow items order and each carries index with result or error, one confirm covers the whole batch, and keyed samples additionally require acknowledge_key_ordering on the item. It exceeds the baseline with cross-parameter interaction guidance.

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 precise verb+resource+scope: 'Increase the partition count of 1 to 100 topics in one call.' The batch framing and the 1-100 bound are concrete. It does not explicitly differentiate from the nearest sibling alter_topic_config, so it stops short of a 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?

Gives clear conditions for use (only increasing counts, ballled with confirm=true to take effect) and the constraint that Kafka cannot remove partitions. No explicit when-to-use-this-vs-alternative routing against siblings like alter_topic_config or create_topic, so not a 5.

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