Surface AI

Edit a draft variant

variant_update

DestructiveIdempotent

Replace a draft variant's contents with the given object. Only drafts can be edited; to change a live variant, create a new one and archive the old.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "surface_id": "<surface_id>",
      "variant_id": "<variant_id>",
      "contents": "<contents>"
    },
    "name": "variant_update"
  }
}

Input Schema

Name	Required	Description
`contents`	Yes	The new contents, in the shape variant_create takes.
`surface_id`	Yes	The surface id, from surface_list.
`variant_id`	Yes	The variant id, from variant_list.

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedNov 12, 2026
- changedInput schema / properties / surface_id / description
```
Previous value: -"The surface id."New value: +"The surface id, from surface_list."
```
First observedNov 11, 2026

TDQS

A4.4/5.0

Behavior4/5

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

Beyond the annotations, the description discloses the draft-only constraint and clarifies that this is a full contents replacement rather than a partial edit. It does not describe permission requirements or the exact failure behavior for non-draft variants, but the destructive and idempotent semantics are consistent with the annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The definition is two tight sentences with the core operation front-loaded. Every sentence adds useful constraint or routing information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a destructive mutation with rich schema coverage and annotations, the description covers the critical draft-only restriction and the live-variant alternative. It does not discuss response behavior or error handling, but no output schema exists and the key calling constraint is present.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, and the description adds little parameter-specific meaning beyond noting the replacement object. The contents shape reference is already present in the schema, so the baseline of 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific verb and resource: replacing a draft variant's contents. It also scopes the tool to drafts and distinguishes the live-variant path, so an agent can tell what this tool does without opening the schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

It explicitly says only drafts can be edited and gives the alternative workflow for live variants: create a new one and archive the old. The when-not condition and alternative path are both stated clearly.

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

All Surface AI tools Inspect

Try in Browser

One endpoint for every MCP toolRayrun runs every MCP server behind one URL and holds the credentials. Each call is decided per client, tool, and argument, then recorded.ray.runAd

Glama MCP Gateway

Add one secure layer between your agents and this server.

Resources

Need Help?