Change the Node.js runtime version for an app (18, 20, or 22). Updates package.json engines.node and restarts the container with the new Node.js image.
| Name | Required | Description | Default |
|---|---|---|---|
| app | Yes | App ID (UUID) or subdomain | |
| version | Yes | Node.js major version to use |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the transparency burden. It discloses key side effects: 'Updates package.json engines.node and restarts the container with the new Node.js image.' This provides useful behavioral context about the mutation and restart, though it does not mention permissions, reversibility, or potential downtime duration.
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?
The description is a single, well-structured sentence that front-loads the main action and then lists the side effects. It is concise with no filler words, every part earning its place.
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 tool with only two parameters and clear schema coverage, the description is largely complete. It explains the core action and side effects. However, it does not mention preconditions (e.g., app must exist) or return behavior, but given the tool's simplicity, this is a minor gap.
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?
The input schema already describes both parameters (app and version) with clear descriptions and an enum for version. The description adds no additional parameter semantics beyond what the schema provides, so the baseline score of 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?
The description clearly states the tool's function with a specific verb and resource: 'Change the Node.js runtime version for an app'. It also explicitly lists the allowed versions (18, 20, or 22), making it distinct from general app update or restart tools.
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 when you need to change the Node.js runtime version, but it does not explicitly state when to use this tool over alternatives like update_app or restart_app, nor does it mention exclusions or prerequisites. The context is clear but not fully elaborated.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Most tools have clearly distinct purposes, but a few pairs could be confused: get_app vs. get_app_status both report on app state, and update_app vs. set_node_version both modify runtime configuration. Descriptions are detailed enough to mitigate most ambiguity, but the overlap is notable.
Tool names largely follow a consistent verb_noun snake_case pattern (e.g., list_apps, create_app, delete_file). Minor deviations include the bare verb 'login' and the noun-first 'git_info', which break the pattern slightly but are still understandable.
At 37 tools, the set is on the heavy side, well above the typical 3-15 range. However, the server covers a broad PaaS domain (auth, app lifecycle, file management, packages, versions, git, metrics), and each tool addresses a distinct operation. It feels over-engineered in places but not gratuitously so.
The tool surface is impressively complete for a deployment platform: authentication, app CRUD, start/stop/restart, file operations (read/write/delete/rename/search/upload), package management, version snapshots and restore, git remote and push/pull, logs, metrics, and configuration. No critical dead-ends are apparent.
