Apply a master spread to a specified page in an open InDesign document, assigning consistent layout elements by page index and master name.
Apply a master spread to a page
| Name | Required | Description | Default |
|---|---|---|---|
| pageIndex | Yes | ||
| masterName | Yes | ||
| document_id | No | Which open document to act on: a name (see document_listOpen) or a 0-based index. Defaults to the front document. |
Changes observed during successful MCP inspections.
v1.6.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden. It does not disclose whether applying a master overwrites existing master-page items, whether the operation is reversible (undo), or what permissions/state is required. For a mutation tool with zero annotation coverage this is a meaningful gap.
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?
A single front-loaded sentence with no filler. It is efficient, though its brevity reflects under-specification rather than tight completeness.
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?
A mutation tool with no annotations, no output schema, and two of three parameters undocumented in both the schema and description is not complete enough for confident invocation. The agent lacks the information needed to know what applying a master does to existing page content.
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 only 33% — only document_id is documented in the schema, while pageIndex and masterName are bare. The description names 'page' and 'master spread' but adds no format, indexing base, or naming semantics to compensate for the undocumented parameters.
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+resource pair ('Apply a master spread to a page'), which is clear about what happens. However it does not distinguish itself from the sibling master_apply, leaving ambiguity about which one an agent should pick.
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?
There is no when-to-use guidance, no prerequisites (e.g. that the master must already exist, see master_list/master_create), and no mention of the near-identical sibling master_apply. The agent must infer the context entirely.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.