filmora_playback

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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the safety profile is partly covered. The description adds a real operational caveat (focus targeting behavior). It never explains why a playback operation is flagged destructive, nor what state changes result, leaving a notable gap against a strong annotation.

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, front-loaded sentences with zero filler; the purpose comes first and the prerequisite second. It is efficient, though arguably under-specified rather than truly complete.

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 low-complexity 2-parameter tool with no output schema, coverage is only partial: purpose and focus precondition are present, but parameter meaning, effect on playhead/save state, and return behavior are absent. Adequate but with clear gaps.

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%, so the description must compensate and it does not. It never mentions the 12-value 'action' enum (though values are self-evident) and says nothing about 'repeat', whose semantics and interaction with frame/second navigation are genuinely non-obvious.

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?

Names a specific category (playback/navigation shortcuts) and the resource it operates on (timeline/player). However, it does not differentiate itself from generic siblings like filmora_key, filmora_command, or filmora_ui_action, which could plausibly issue the same keystrokes. The enum in the schema supplies the specifics the prose omits.

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?

Provides a genuine usage precondition: focus the timeline/player first, otherwise navigation is meaningless. But it offers no when-to-use vs alternatives guidance relative to the key/command/ui_action siblings, so routing is left to inference.

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