get_incumbent

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

With no annotations, the description carries the full burden and does so well: it declares read-only explicitly, discloses that the value is derived and never stored, gives the derivation rule ('latest promote not superseded by a rollback'), and defines the empty case. It stops short of mentioning pagination or error behavior, but the behavioral profile is largely covered.

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?

Three tight sentences with the operation and read-only constraint front-loaded, then the derivation rule, then the empty-state edge case. No filler and every sentence adds distinct information.

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?

Output schema exists, so return format need not be described. Combined with zero parameters and full coverage of the derivation and empty semantics, an agent has everything needed to call and interpret this tool 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?

The tool takes zero parameters, so per the rubric the baseline is 4. There is nothing for the description to clarify beyond what the empty schema already communicates.

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?

States a specific verb and resource ('Derive the incumbent candidate') and immediately scopes it as read-only. It goes further by defining the domain concept itself (champion/challenger), so an agent knows exactly what it retrieves and how it differs from siblings like get_candidate or list_promotion_decisions.

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?

It explains the semantic state this tool answers for and notes the empty-until-first-promote condition, which implicitly tells an agent when it applies. However, it never names an alternative or states when to prefer get_candidate / list_promotion_decisions instead, so routing guidance is only implied.

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