add_keyframe_to_property_track

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

Annotations already declare the mutation profile (readOnly=false, destructive=false, idempotent=false), so the bar is lower. The description adds real context beyond that: the value is broadcast onto every channel of the section, keys_added/channel_count are reported, and a saved/save_error pair reveals auto-save behavior. It stops short of explaining duplicate-key behavior implied by idempotentHint=false.

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 purpose well and the inline return shape is warranted given no output schema exists. But the sentence 'The value is keyed onto every channel of the section:' terminates in a dangling colon, indicating truncated or malformed text that harms structure.

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 no output schema, the inline return shape (key_frame, keys_added, channel_count, saved, save_error) supplies the result contract the schema cannot, and the prerequisite is stated. Minor gaps remain: no note on what happens when a key already exists at that time, which matters given idempotentHint=false.

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 100%, so the schema already documents all five parameters (value types, time >= 0, property_type enum values, GUID meaning). The description only adds the channel-broadcast note for value, which is marginal beyond the schema; baseline 3 is appropriate.

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?

States a specific verb and resource (adds a keyframe to a property track's section channel) plus the timing dimension, and names the prerequisite sibling add_property_track. It does not explicitly contrast with the other keyframe-adding siblings (add_transform_keyframe, add_weighted_value_keyframe), but 'property track' is a distinctive enough target resource to identify it.

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 one clear prerequisite ('call add_property_track first'), which is genuine workflow guidance. However, it never says when to prefer this over the sibling keyframe tools or when it is inapplicable, so an agent must infer the rest.

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