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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is covered. The description adds two things annotations cannot: results are page-bounded, and the returned source_revision/version must be retained for later edits — a meaningful optimistic-concurrency hint since there is no output schema documenting these fields.

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 short sentences with no filler, and the primary action is front-loaded before the operational caveat about retaining revision fields. Every clause carries 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?

With no output schema, the description partially compensates by naming source_revision and version, which are return values. But for a 6-parameter tool with zero schema documentation, it omits the identifier relationships (film/track/episode) and gives no sense of what a cue page contains, so it is only minimally complete.

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% across 6 parameters, so the description must carry the burden. It only implicitly explains draft ("saved draft" vs "automatic subtitle cues") and pagination ("bounded page"); it says nothing about film_id, track_id, or when episode_id is required, leaving the three identifier parameters entirely undocumented.

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 gives a specific verb and resource ("Read a bounded page of automatic subtitle cues or a saved draft") and distinguishes two data sources via the draft flag. It does not name sibling tools such as list_film_subtitles or edit_subtitle_cues, so the distinction from siblings is only implied by "for editing."

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?

"Retain source_revision and version for editing" implies the tool is used as a precursor to edit_subtitle_cues, which is useful implied guidance. However, it never states explicitly when to prefer this over list_film_subtitles or when a draft vs. automatic track should be fetched, leaving the selection logic to inference.

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