auth_get_user

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

With no annotations, the description carries the full burden for behavioral disclosure. 'Get' implies a read-only operation, but the description does not disclose error behavior (e.g., what happens if the identifier is not found), authentication requirements, or return format. It adds no context beyond the minimal implication of a read.

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 a single, complete sentence that directly states the purpose and key input detail. Every word contributes value, with no filler or redundant content.

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?

The tool has a simple structure (1 param, no output schema), and the description adequately conveys the basic operation. However, the absence of any return-value description, error semantics, and usage context means the agent gets only a minimal understanding. It is sufficient for a simple getter but leaves clear gaps.

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 only defines 'identifier' as a string with zero description, so the description must compensate. It does so by explicitly stating that the identifier can be an 'email or localId', adding meaningful domain semantics that help the agent construct the parameter correctly. This goes beyond the bare schema but could be improved with format examples.

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 a specific verb ('Get') and resource ('a single Auth user') with a differentiating scope ('by email or localId'). It distinguishes this tool from siblings like auth_list_users (list vs single) and firestore_get/rtdb_get (Auth vs other data stores).

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 gives no guidance on when to use this tool versus alternatives like auth_list_users or firestore_get. It does not mention any exclusions, prerequisites, or typical use cases, leaving the agent to infer from the name and sibling context.

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