add_frames

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

Annotations declare readOnlyHint=false and destructiveHint=false, correctly signaling a non-destructive mutation. The description adds genuinely useful context beyond that: the default of copying the previous frame's cels and the empty=true override. It omits save/backend behavior, but that is documented in the schema.

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 tight sentences, zero filler, with the primary action front-loaded and the key behavioral default immediately following.

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 mutation tool with annotations and no output schema, the description covers the core default behavior adequately but leaves the return value, batch-mode effects, and sibling routing unaddressed. It is minimally sufficient rather than 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 coverage is 63%, with 'empty', 'count', and 'durationMs' lacking descriptions. The description compensates for 'empty' (blank vs copied frames) and hints at copyFrom's default, but says nothing about count or durationMs, so it only partially bridges the gap.

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?

'Adds frames' states a specific verb and resource, clearly distinguishing it from delete_frames and move_frame. The added clause about cel-copying behavior further sharpens what the operation does, though it never explicitly names a sibling to route against.

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 implies usage via the 'empty=true adds blank frames' distinction, which steers the agent toward the right option for blank vs cloned frames. However, it offers no explicit when-to-use guidance relative to copy_cel/link_cels or any prerequisites, leaving routing to inference.

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