set_subtitle_cue_text

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

Annotations already flag the mutation profile (destructive, idempotent), but the description adds real context: it loads the asset, range-checks cue_index, writes Subtitles[cue_index].Text, and persists via save. It also supplies a return shape, useful since no output schema exists. Only missing piece is what happens when cue_index is out of range (error vs no-op).

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?

Two compact sentences: the purpose and internal flow come first, the return shape second. No filler, no redundancy. Slightly terse on edge cases, but well front-loaded.

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 3-param mutation tool with no output schema, the description covers the mutation target, validation, persistence, and the return payload, while annotations carry the safety profile. The main gap is the out-of-range cue_index outcome, which an agent would benefit from knowing.

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 schema already documents text, cue_index, and asset_path, establishing the baseline of 3. The description adds the range-validation behavior for cue_index but no format or syntactic detail beyond the schema.

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 precise verb+resource ("Sets the text on an existing subtitle cue") and even enumerates the internal operation sequence. An agent can distinguish this from set_subtitle_cue_timing or add_subtitle_cue by the explicit focus on the text field, though no sibling is named directly.

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 word "existing" implies the cue must already be present, but there is no explicit when-to-use, when-not-to-use, or routing to siblings such as add_subtitle_cue for new cues. No prerequisites or alternative guidance are provided.

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