caption_span_ls

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

Annotations already declare readOnlyHint and idempotentHint, and the description's 'Read-only' merely repeats that. But it adds genuinely new behavioral detail: 'later ones winning' indicates precedence among overlapping spans, and 'where each plays now' describes the current placement. These go beyond the annotations and outline non-obvious behavior.

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 compact and free of filler; every clause contributes meaning except 'Read-only,' which duplicates the annotation. The phrasing is terse to the point of being cryptic, but the structure is appropriately short.

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 that an output schema exists and the path parameter is fully documented, the description covers the essential semantic points: it enumerates spans, expresses precedence via 'later ones winning,' and indicates positional output. It does not elaborate on ordering or format, but the output schema can carry that burden.

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%, and the single `path` parameter is documented thoroughly in the schema itself. The description adds no parameter information, which is acceptable under the baseline for fully documented schemas.

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 identifies the resource ('every caption span') and one returned attribute ('where each plays now'), so an agent can infer this is an inventory/list operation. However, it never states an explicit verb such as 'list' or 'return,' and 'later ones winning' is unexplained shorthand that could confuse an agent about what the tool actually does.

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?

No guidance is given about when to use this tool versus siblings like caption_span_add, caption_span_rm, or caption_view. The read-only annotation implies it is safe for inspection, but the description does not state selection criteria or mention alternatives.

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