index_split

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions the constraint about shard count multiples, which is useful behavioral context. However, it doesn't describe whether this is a destructive operation (likely yes, as it creates a new target index), what permissions are required, whether the source index remains accessible during the operation, or what happens to existing data. For a mutation tool with zero annotation coverage, this leaves significant behavioral gaps.

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 description is efficiently structured with a purpose statement followed by parameter explanations and a constraint note. Every sentence adds value, though the formatting with extra whitespace could be cleaner. It's appropriately sized for a 3-parameter tool with a specific constraint.

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 complex index mutation tool with 3 parameters, no annotations, and no output schema, the description is incomplete. It explains parameters adequately but lacks crucial context about the operation's behavior, side effects, error conditions, and expected outcomes. The agent would need to guess about many aspects of how this tool actually works and what it returns.

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?

With 0% schema description coverage, the description compensates well by explaining all three parameters in Chinese: 'source' (源索引名称), 'target' (目标索引名称), and 'settings' (目标索引设置). It adds crucial semantic context that the settings must include 'number_of_shards'. This goes significantly beyond what the bare schema provides, though it doesn't explain the format or constraints of the settings object beyond the shard requirement.

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 clearly states the tool's purpose: '拆分索引（增加分片数）' translates to 'Split index (increase number of shards)'. It specifies the verb ('split') and resource ('index') with the specific goal of increasing shard count. However, it doesn't explicitly differentiate from sibling tools like 'index_shrink' or 'index_clone' which also modify indices.

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?

The description provides no guidance on when to use this tool versus alternatives. While it mentions a constraint ('新分片数必须是原分片数的倍数' - 'new shard count must be a multiple of original shard count'), it doesn't indicate when this operation is appropriate compared to other index modification tools in the sibling list, nor does it mention prerequisites or typical use cases.

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