update_hda

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

With no annotations, the description carries the full burden and does disclose the side effect: the definition's library file is written by this call, and it names the response fields `saved_to_disk` and `library_file_mtime` that report it. It also explains the embedded-definition case (lives in the hip file, kept on scene save). It omits permissions/prerequisites and error behavior.

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 core purpose and two efficient sentences about file-vs-embedded behavior. The trailing Args block is largely boilerplate (ctx: MCP context) and does little work, but the entry is otherwise tight.

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?

No annotations and no output schema, yet the description covers the mutation's side effects and even names the return fields that report them, plus the embedded-definition nuance. What remains missing – error cases when the node has no HDA definition and permission requirements – is minor for a single-parameter write.

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 0% and the single node_path parameter has no schema description. The 'Args' section merely restates 'node_path: Node path.' rather than adding meaning. The description's mention of 'the current node' implies node_path targets a node with an HDA definition, but that is thin compensation for the coverage 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?

States a specific verb and resource: 'Save the current node contents back to its HDA definition.' Clear and unambiguous, and distinct from siblings like reload_hda or edit_hda_interface. However, it never names an alternative, so the differentiation from siblings is left implicit.

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?

"no separate save is needed" gives a useful usage hint by preempting a save_scene call, and the embedded-definition note implies when the write survives. But there is no explicit guidance on when to use this versus reload_hda, edit_hda_interface, or set_hda_interface. Usage is only implied.

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