Create combat encounter

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

Annotations declare readOnlyHint=false and idempotentHint false, so the mutation nature is already implicit in the annotations; the description adds valuable behavioral context. It explicitly states the encounter is not started automatically and that tokens are specified by id only, which goes beyond the schema and annotations. It doesn't mention permissions or failure cases, but the added context is meaningful.

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 sentences with no filler. The main action and default behavior are front-loaded, followed by the key exclusion, and the token-specific constraint. Every sentence earns its place.

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 no output schema exists, the description covers the essential operational behavior well: creation, default scene, optional token list, and the start-combat separation. It doesn't hint at return value details, which the agent may need to later reference the created encounter, but the core invocation context is sufficiently complete for the tool's complexity.

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 baseline of 3 applies. The description repeats the scene default and token id idea, but these are already in the sceneIdentifier and tokenIds schema descriptions. It adds no new parameter-level semantics beyond what the schema already provides.

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: creates a combat encounter on a scene. It also clarifies scope with details like the active-scene default and optional token combatants, and distinguishes itself from start-combat in the next sentence. The description clearly separates creating an encounter from starting the encounter.

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?

Explicitly states the main condition of use: creating a combat encounter on a scene, with the active scene as default. It names the key alternative alternative explicitly: "It does not start the encounter; start-combat does." The token handling note also gives practical guidance for how to provide tokens.

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