combat_start

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

With no annotations, the description carries the full burden and does well: it discloses state changes (combat opens, first actor's turn is already open), dice outcome effects, and a critical ordering rule about not resolving an attack before the opposition acts. It does not cover edge cases like repeated calls, but it is substantially transparent.

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 efficiently structured and front-loaded with the core action. The initiative outcomes and follow-up handling earn their place, though the multiple paragraphs could be slightly tightened without losing 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?

For a combat-start tool with no output schema and no annotations, the description covers the essential invocation context: prerequisites, return behavior (first turn open), initiative consequences, and how to handle the opposition acting first. The main omission is the meaning of the optional stakes and reason parameters, but core usage is complete enough.

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 0%, so the description must compensate. It usefully explains initial_ranges values and implies pc_ids/npc_ids, but the reason and stakes_* parameters remain entirely unexplained, leaving a meaningful semantic gap for optional parameters.

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 opening sentence, 'Open combat and roll initiative,' states a specific verb and resource while clearly separating this tool from siblings like combat_begin_turn and combat_close. It also describes the initiative mechanism, making the tool's purpose unmistakable.

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 concrete workflow guidance: create NPCs first, follow next_step when the first turn opens, and use combat_defend when the opposition acts first. It does not explicitly contrast with alternatives like combat_attack or combat_begin_turn, but the sequencing and branch behavior are clear.

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