list_oncall_users

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions retrieval capabilities but fails to describe critical behaviors such as pagination handling (implied by the 'page' parameter), authentication requirements, rate limits, or the format of returned data. For a read operation with zero annotation coverage, this is a significant gap in transparency.

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, efficient sentence that front-loads the core purpose ('List users from Grafana OnCall') and succinctly explains the key functionalities. There is no wasted verbiage, and every part of the sentence contributes directly to understanding the tool's scope and options.

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 complexity of a list/retrieve tool with three parameters and no output schema, the description is incomplete. It lacks details on behavioral aspects (e.g., pagination, auth), doesn't explain the return format, and offers minimal guidance on usage. With no annotations to compensate, the description fails to provide sufficient context for an agent to use the tool effectively beyond basic parameter input.

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%, so the input schema already documents all three parameters ('page', 'userId', 'username') with clear descriptions. The description adds marginal value by summarizing the filtering options ('all users, a specific user, or filter by username'), but it doesn't provide additional syntax, format details, or usage examples beyond what the schema offers. This meets the baseline for high schema coverage.

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 the verb ('List') and resource ('users from Grafana OnCall'), making the purpose evident. It distinguishes the tool by specifying it can retrieve all users, a specific user, or filter by username, which helps differentiate it from sibling tools like 'list_users_by_org' or 'get_current_oncall_users'. However, it doesn't explicitly contrast with these siblings, so it's not a perfect 5.

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 implies usage scenarios (retrieving all users, a specific user, or filtering by username), but it doesn't provide explicit guidance on when to use this tool versus alternatives like 'get_current_oncall_users' or 'list_users_by_org'. No exclusions or prerequisites are mentioned, leaving the agent to infer context from the tool name and parameters alone.

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