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

Annotations already declare destructiveHint=true and readOnlyHint=false, and the description corroborates rather than contradicts them by disclosing the overwrite rule ('A template of the same name is replaced') and the scope boundary ('never its words'). It does not mention permission or ownership requirements for saving from an edit, which is the main remaining gap for a mutation.

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-loaded with the verb and the outcome, then the scoping parenthetical, then the sibling pointer. The parenthetical list is dense but every item earns its place by defining 'look'; the only slight drag is the stacked clauses in a single long sentence.

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 two-parameter mutation with an output schema and full annotation coverage, the description supplies everything needed: what is captured, what is not, how name collisions resolve, and where to find the results. Return values are correctly left to the output schema.

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 100%, so both edit_id and name are already documented, and the description largely restates them ('saves the look of one video edit', 'under a name'). The one piece of added meaning — that the name is the replacement key — is really behavioral rather than parameter-level semantics.

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 (save one edit's look as a template) and then enumerates exactly what 'look' means — format, captions, hook style/length, framing per clip kind, pause tightness, closing phrase — while explicitly excluding the words. It is clearly distinguishable from postkey_list_edit_templates and from postkey_edit_video.

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 the purpose-driven context ('so the person can start new edits from it') and routes to the sibling for the adjacent task ('List them with postkey_list_edit_templates'). It stops short of stating exclusions, such as when to prefer postkey_list_video_templates or postkey_start_edit instead.

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