insert_media

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

No annotations exist, so the description carries the whole burden. It does disclose meaningful side effects — insert splits the storyline and pushes later clips right — which is exactly the kind of ripple consequence an agent needs. It is silent on prerequisites (must a timeline be open?), failure behavior for bad paths, and whether the operation is undoable, which are significant gaps for a mutation tool with zero annotation coverage.

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?

Front-loads the core action in one sentence, then spends the remaining clauses entirely on mode semantics and parameter meaning. No filler, no restatement of the name, and the highest-value distinguishing information comes first.

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 7-parameter mutation tool with no annotations and no output schema, the description covers the decisions that matter most (mode, time, trim range, role). The notable hole is the lane parameter, which is referenced only indirectly through "lane 1" / "lane -1" in the connect explanation and never defined as an input.

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 largely does: mode values are decoded with real semantics, time is tied to connect placement, source_in/duration are explained as selecting the portion of the file, and role gets a concrete example ("music"). lane and path remain unexplained, leaving two of seven parameters to be inferred.

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?

Opens with a specific verb+resource ("Add a media file to the timeline") and immediately disambiguates the three modes with concrete spatial semantics (above/below the storyline, splits and pushes later clips, appends to end). An agent can distinguish this from siblings like add_title, split_clip or move_clip without opening the schema.

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?

Gives explicit selection guidance among the mode values with the practical outcome of each (connect = B-roll or music, insert = ripple, append = tail). It does not name alternative tools or state when not to use this tool versus e.g. add_title for titles or move_clip for repositioning, so it stops short of full when/when-not guidance.

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