es_index_doc

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

No annotations are provided, so the description must bear the burden. It discloses that the tool creates or overwrites a document and is blocked in readOnly mode. However, it does not detail other behavioral traits such as required permissions, error behavior, or return value format.

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 concise: two sentences, no redundant words. The first sentence defines the action, the second adds a critical constraint. Every word serves a purpose.

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?

With no output schema, the description should clarify what the tool returns (e.g., the indexed document ID or result). It also lacks explanation of behavior when a document with the same ID exists (overwrite) vs. auto-generated ID (create). This leaves the agent unsure of the response and the exact semantics of create/overwrite.

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?

The input schema already defines all 4 parameters with descriptions (100% coverage). The tool description itself adds no additional parameter-level information beyond the schema, so it meets the baseline but does not elevate it.

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 'Index (create or overwrite) a document' which specifies the action and resource. It implicitly distinguishes from sibling tools like es_get_doc (read-only), es_search (querying), and es_delete_doc (deletion) by focusing on creation/overwrite.

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 mentions a blocking condition ('Blocked when that connection's own readOnly mode is enabled'), which provides a when-not-to-use context. However, it does not explicitly direct when to use this tool over alternatives like es_bulk_index (for multiple documents) or es_update_doc (for partial updates).

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