Create Index

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

Beyond the annotations, it discloses that the call blocks until the index is ready for upserts and queries, removing the need for readiness polling, and that an existing index of the same name is returned unchanged instead of erroring – which is concrete confirmation of the idempotentHint and a real operational constraint. These are exactly the facts an agent needs and cannot get from the annotation block 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?

Specific purpose and blocking behavior are front-loaded, and the sibling pointer comes last where a routing note belongs. The only mildly expendable sentence is the AWS/GCP/Azure cloud mention, which the cloud enum already carries, but it costs little.

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 blocking, mutating create operation with no output schema, the description covers the essentials: what gets created, the embedding requirement, latency/readiness implications, idempotent behavior on name collision, and the sibling alternative. Nothing an agent needs in order to call 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 description coverage is 100%: name, cloud, region, embed, model, and fieldMap all carry their own documentation, including the cloud enum and per-model explanations. The description adds only the framing that embedding targets the fieldMap 'text' field, which the schema largely states already. The analytics-only llm_model/llm_provider parameters are not touched on at all, so nothing is compensated beyond baseline.

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 definition states a specific verb and resource ('Create a Pinecone index with integrated inference'), explains the defining mechanism (auto-embedding the text field named in fieldMap), and explicitly contrasts itself with the sibling create-document-index. An agent can distinguish it from list-indexes, describe-index, and upsert-records without opening a schema.

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?

It names an alternative (create-document-index) and the condition that favors it (full-text search plus integrated embedding on the same field), which is exactly the kind of routing signal an agent needs. However, 'For a new index, prefer create-document-index' leaves this tool's own best-fit scenario undefined – an agent may wonder whether this tool is legacy-only, which weakens the when-to-use picture rather than completing it.

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