Godot MCP Server

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

The description adds valuable behavioral context beyond annotations: it explains that the tool creates a child node within a parent scene, specifies default behaviors (node_name defaults to scene file's stem, target_scene_path defaults to active scene), and describes the return format ('{ name, type, path } of the instantiated node'). Annotations already indicate this is a non-destructive, non-idempotent write operation, but the description enriches this with implementation details.

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 perfectly structured and front-loaded: the first sentence states the core purpose, followed by organized sections (Args, Returns, Examples) with zero wasted words. Every sentence serves a clear purpose, from explaining parameters to providing practical usage guidance.

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 5 parameters, no output schema, and annotations covering basic safety hints, the description is remarkably complete. It explains what the tool does, when to use it, all parameter meanings with examples, return format, and includes a practical use case. The combination of description and annotations provides everything needed for an agent to use this tool effectively.

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?

With 100% schema description coverage, the baseline is 3, but the description adds meaningful semantic context: it clarifies that 'scene_to_instantiate' must be a '.tscn file', provides concrete path examples ('res://enemies/goblin.tscn'), explains default behaviors for optional parameters, and shows how 'properties' can be used to set position in the example. This goes beyond the schema's technical descriptions.

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 specific action ('Instantiates an existing .tscn file as a child node inside another scene') with the exact resource type (.tscn files) and distinguishes it from siblings like godot_add_node (which likely creates new nodes) or godot_create_scene (which creates new scenes). The verb+resource combination is precise and unambiguous.

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 includes an explicit 'Examples' section with a 'Use when' scenario that demonstrates the tool's application ('Add a Goblin enemy to the level at position (300, 100)'), providing concrete guidance on when to use this tool. While it doesn't explicitly mention alternatives, the example implicitly distinguishes it from tools like godot_set_node_property (which modifies existing nodes).

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