concatenate

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

With no annotations, the description carries the full burden of behavioral disclosure. It discloses the same-kind requirement and the ordering behavior, but does not state whether the operation creates a new clip, modifies inputs, or is reversible. It also doesn't mention side effects or return behavior beyond the existence of an output schema. This gap is significant for a tool that likely creates a new resource.

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 two short sentences that immediately state the core function and the most critical constraint. Every sentence earns its place; no filler or redundancy.

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?

The tool has moderate complexity with an output schema and full parameter coverage. The description covers the main purpose and a key constraint but lacks explicit behavior on output creation or edge cases (e.g., empty list). It's adequate for basic use but not comprehensive.

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?

The schema covers 100% of parameter descriptions (clip_ids and method). The description adds no parameter-specific meaning beyond what the schema already provides—it simply restates the order for clip_ids and the type constraint. Baseline 3 applies because the schema does the heavy lifting.

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 clearly states the action: 'Join clips end-to-end, in the given order.' This is a specific verb (join) with a clear resource (clips) and an ordering constraint. It distinguishes from sibling tools like overlay_clip or trim which do different operations.

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 description gives an implied usage context: concatenating clips in sequence. It also mentions a key constraint (all ids must be same kind). However, it does not explicitly state when to prefer this over alternatives (e.g., overlay_clip for compositing) or specify exclusions beyond the kind matching. The guidance is minimal.

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