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

With no annotations provided, the description carries the burden of disclosing behavior. It indicates a read-only operation ('Retrieve') and provides useful context by stating 'in real-time' and specifying the output contents (primary/secondary on-call, contact info, rotation schedules). This goes beyond a minimal label but could further mention caching or absence handling.

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, well-structured sentence that front-loads the primary action and then adds concise clarifying details. Every phrase contributes to understanding the tool's function without redundancy.

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 description is sufficient for a simple read-only tool with fully documented parameters. It covers the key output areas (personnel, contact info, rotation) and the real-time nature. The lack of an output schema is compensated by the description's detail, but it could mention error cases or prerequisites for completeness.

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?

Both parameters are fully described in the schema (100% coverage), including the dual meaning of 'tagOrId' and the purpose of 'context'. The tool description adds no extra parameter semantics, so the baseline of 3 applies since the schema does the heavy lifting.

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 ('Retrieve') and resource ('current on-call personnel for an entity'), and it distinguishes itself from sibling tools by exclusively addressing on-call personnel. The additional detail about primary/secondary and contact information reinforces the specific purpose.

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 when to use the tool (when real-time on-call status is needed) and clarifies it returns active responsibility for incident response. However, it does not explicitly mention alternatives or state when not to use it, leaving the guidance implicit rather than explicit.

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