reindex

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

Goes well beyond the annotations by disclosing asynchronous execution, task_id polling, environment flag requirements, and the mandatory confirm parameter. It also orients the agent to handle the operation as non-though and non-idempotent, which is critical for a rebuild/restore-style action.

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?

Three sentences that pack a functional summary, use-case routing, asynchronous behavior, and prerequisites into a compact structure. No padding or redundant restatement of the tool name.

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?

Describes what the operation does, when to use it, how it runs, and what is required before calling it. Lacks explicit detail on destination index behavior and tuning parameters like slices, but for a modal-input tool the guidance is solid and actionable.

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 coverage, the description compensates by explaining the roles of core params: query, pipeline/script, wait_for_completion, confirm, source/dest indexes. It does not comment on slices, requests_per_second, or op_type, but their names are self-explanatory and the main semantics are covered.

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?

Clearly states the operation: 'Copy documents from a source index to a destination,' with optional filtering and transformation. The use cases 'change a field type, reshard, or migrate data' make the tool's role unmistakable and distinguish it from sibling data-manipulation tools.

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 explicit when-to-use guidance ('Use this to change a field type, reshard, or migrate data') and specifies prerequisites such a = 'confirm=true' and 'ES_MCP_ALLOW_DESTRUCTL=true.' Does not name explicit alternative tools or when-not-to-use scenarios, so it stops short of a 5.

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