resolve_create_chapter_markers

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

With no annotations, the description carries the transparency burden and does meaningful work: it discloses that validation happens for the complete batch before any write, that frame positions are timeline-relative integers, and that no transcript or speaker-time inference is performed. It does not describe return values or failure behavior, so it is not maximally 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?

Four short sentences deliver the action, entry contract, validation behavior, and non-goals. The information is front-loaded and every sentence contributes something that the schema and annotations do not already provide.

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 covers the input contract, coordinate frame, and validation atomicity, which is enough for invoking the tool with correct arguments. However, there is no output schema and no statement about what the tool returns (success, created marker IDs, count) or how failures are surfaced, so an agent cannot fully predict the result.

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%, and the description compensates by defining the structure of each chapters entry: frame as a timeline-relative integer, name as a string, and note as an optional string. It does not explain the color parameter beyond the schema default, but color's meaning is reasonably self-evident and it is optional.

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 states a precise action ('Create markers') with a specific input source ('supplied chapter/speaker boundaries') and gives the per-entry shape. It also distinguishes this tool from nearby transcription or inference tools by explicitly noting that it does not extract transcripts or infer speaker times.

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 the tool is for cases where chapter/speaker boundaries already exist and tells the agent not to use it for transcript extraction or speaker-time inference. It does not explicitly name alternative tools or provide full when-not-to-use conditions, but the context is clear enough for good routing.

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