list_users

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

With no annotations provided, the description carries the transparency burden. It clearly marks the operation as read-only, describes the return format, discloses that truncated is measured via an extra fetch, and states the null convention for missing IdP fields. It stops short of describing authentication requirements or error cases, but for a read-only list tool this is quite thorough.

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 front-loaded with a clear summary and uses structured sections (Args, Returns). Every sentence provides value, including the truncation nuance and null convention. It is appropriately sized for a tool with three parameters and an edge case.

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 (multi-IdP normalization, pagination, null handling) and the absence of an output schema, the description covers all essential aspects: purpose, parameters, return structure, truncation detection, and field conventions. An agent has enough information to invoke and interpret results correctly.

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 coverage is 0%, so the description is the only source of parameter meaning. It explains search as a username/email search, max_results as a page bound with a default, and target as an IdP name from config with a default if omitted. This fully compensates for the schema's lack of descriptions.

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 specifies a clear action (list users) with a defined scope (in the realm, normalized across Keycloak/authentik). The [READ] prefix and explicit reference to 'users' distinguishes it from sibling tools like list_clients or list_groups.

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?

Provides context for when to use the tool (realm-wide user listing, normalized across IdPs) and covers pagination behavior ('re-run with a higher max_results before drawing a realm-wide conclusion'). It does not explicitly name alternatives or exclusion cases, but its purpose is clear enough for an agent to select it appropriately.

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