put_mapping

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

Annotations declare destructiveHint=true and readOnlyHint=false, and the description adds strong behavioral context: only additive changes are possible, field-type changes require reindex, writes must be enabled, and confirm=true is required. This goes well beyond the annotations and gives an agent a clear picture of the mutation's constraints.

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 short, dense sentences with no repetition or filler. The main purpose is front-loaded, the key limitation is stated second, and the invocation prerequisite closes it. Every sentence earns its place.

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?

Given the tool's complexity, the description covers the most operationally important context: what the tool does, when it cannot work, and what prerequisites must be met. It is slightly less complete on the exact expected shape of the properties parameter, which the schema leaves entirely open.

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 0%, so the description must compensate. It does by associating properties with new fields and index with an existing mapping, and it explicitly says confirm must be true. It does not give an example or exact format for the properties parameter, which keeps it from being a 5.

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 opens with a specific verb and resource: 'Add new fields to an existing index mapping.' It clearly distinguishes the tool from reindex by stating that changing an existing field type requires reindex, so an agent can correctly select this tool for additive mapping changes only.

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 explicitly says when this tool is appropriate (additive mapping changes) and when it is not (changing existing field types requires reindex). It also states the operating prerequisites: the server must have writes enabled and confirm=true must be provided.

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