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update-setting-value

Update a feature flag or setting value in a specific environment using JSON Patch operations, modifying only the specified attributes.

Instructions

This endpoint updates the value of a Feature Flag or Setting with a collection of JSON Patch operations in a specified Environment.

Only the value, rolloutRules and percentageRules attributes are modifiable by this endpoint.

The advantage of using JSON Patch is that you can describe individual update operations on a resource without touching attributes that you don't want to change. It supports collection reordering, so it also can be used for reordering the targeting rules of a Feature Flag or Setting.

For example: We have the following resource.

{
  "rolloutPercentageItems": [
    {
      "percentage": 30,
      "value": true
    },
    {
      "percentage": 70,
      "value": false
    }
  ],
  "rolloutRules": [],
  "value": false
}

If we send an update request body as below:

[
  {
    "op": "replace",
    "path": "/value",
    "value": true
  }
]

Only the default value is going to be set to true and all the Percentage Rules are remaining unchanged. So we get a response like this:

{
  "rolloutPercentageItems": [
    {
      "percentage": 30,
      "value": true
    },
    {
      "percentage": 70,
      "value": false
    }
  ],
  "rolloutRules": [],
  "value": true
}

The rolloutRules property describes two types of rules:

  • Targeting rules: When you want to add or update a targeting rule, the comparator, comparisonAttribute, and comparisonValue members are required.

  • Segment rules: When you want to add add or update a segment rule, the segmentId which identifies the desired segment and the segmentComparator members are required.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
environmentIdYesThe identifier of the Environment.
settingIdYesThe identifier of the Setting.
reasonNoThe reason note for the Audit Log if the Product's "Config changes require a reason" preference is turned on.
requestBodyYes
Behavior3/5

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

No annotations provided, so the description carries the full burden. It discloses modifiable attributes, explains rollbackRules sub-types, and mentions the reason note for audit logs. However, it lacks details on idempotency, error handling, permissions, or rate limits.

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

Conciseness4/5

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

The description is well-structured with paragraphs and a clear example, though it is somewhat lengthy. It front-loads the purpose and uses the example effectively to clarify usage without redundancy.

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 complex tool involving JSON Patch, the description covers the essential aspects: purpose, modifiable fields, operation mechanics, and an example. No output schema exists, but the example illustrates the return structure. Minor gaps remain regarding error responses and behavior for invalid patches.

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

Parameters4/5

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

Schema coverage is high (all parameters described in schema), but the description adds significant value by explaining JSON Patch operations, which attributes are modifiable, and providing an illustrative example. It also details the two rollbackRules types, going beyond the schema's minimal descriptions.

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 clearly states it updates a Feature Flag or Setting using JSON Patch operations, specifies modifiable attributes (value, rolloutRules, percentageRules), and provides a detailed example. This distinguishes it from sibling tools like replace-setting-value or post-setting-values.

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

Usage Guidelines4/5

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

The description explains when to use JSON Patch for selective updates and lists modifiable attributes, but does not explicitly compare to alternative tools such as replace-setting-value or update-setting-value-v2, nor does it state when not to use this endpoint.

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

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