# Color picker

- Human page: https://happytails.ai/en/design-tools/color-picker/
- Markdown: https://happytails.ai/en/design-tools/color-picker.md
- Structured JSON: https://happytails.ai/agents/en/design-tools/color-picker/index.json
- Visibility: public

## Tool capabilities

| Property | Value |
| --- | --- |
| Tool ID | `color-picker` |
| Category | design-tools |
| Implementation | Registered implementation. Registration alone is not a production-quality guarantee. |
| Browser execution | Automatic updates after valid input or file selection. |
| Browser processing | Browser; see tool notes for network behavior. |
| HTTP API | /api/v1/tools/color-picker/run |
| Browser-agent interface | run_current_tool |

### Inputs and settings

Text input: Color value.

Example or placeholder shown in the interface (not a validated fixture):

```text
#3366cc
```

Enter a hex color or use the color picker. Results update as you type. Up to 1,000,000 characters.

| Setting | Meaning | Control type | Default | Constraints |
| --- | --- | --- | --- | --- |
| `color` | Color | color | "#3366cc" |  |

### HTTP contract

API calls process supplied data on the server. The website origin is `https://happytails.ai`. Server API hosting is not connected on the public website yet. Use your local server origin to test these requests.

```http
POST https://happytails.ai/api/v1/tools/color-picker/run
Content-Type: application/json
```

[Detailed operation reference](https://happytails.ai/en/api/tools/color-picker.md) · [Shared API guide](https://happytails.ai/en/api.md)

#### Limits

| Limit | Value |
| --- | --- |
| request_bytes | 8388608 |
| input_characters | 1000000 |
| files_bytes | 5242880 |
| max_files | 0 |
| timeout_seconds | 12 |

#### Complete input schema

```json
{
  "type": "object",
  "additionalProperties": false,
  "properties": {
    "input": {
      "type": "string",
      "maxLength": 1000000,
      "default": "",
      "description": "Plain text input. File tools use files instead unless otherwise documented."
    },
    "options": {
      "type": "object",
      "additionalProperties": false,
      "properties": {
        "color": {
          "type": "string",
          "description": "Color",
          "default": "#3366cc"
        }
      }
    }
  }
}
```

#### Complete output schema

```json
{
  "type": "object",
  "required": [
    "tool",
    "result"
  ],
  "properties": {
    "tool": {
      "type": "string"
    },
    "result": {
      "type": "object",
      "required": [
        "text",
        "files"
      ],
      "properties": {
        "text": {
          "type": [
            "string",
            "null"
          ]
        },
        "data": {
          "description": "Parsed JSON when the textual result is JSON."
        },
        "name": {
          "type": "string"
        },
        "mime": {
          "type": "string"
        },
        "files": {
          "type": "array",
          "items": {
            "type": "object",
            "required": [
              "name",
              "mime",
              "bytes",
              "base64"
            ],
            "properties": {
              "name": {
                "type": "string"
              },
              "mime": {
                "type": "string"
              },
              "bytes": {
                "type": "integer"
              },
              "base64": {
                "type": "string",
                "contentEncoding": "base64"
              }
            }
          }
        }
      }
    }
  }
}
```

#### Error and retry handling

Failures return a non-200 status and `error.code` plus `error.message`. Correct invalid input before retrying; retry server-busy responses with bounded backoff. Returned files contain Base64 data, not persistent download URLs. Decode and inspect the output before treating conversion as successful. See the shared API guide for the complete status and timeout rules.

### Browser-agent workflow

1. Open the human page in a browser that supports WebMCP.
2. Discover the interface exposed by that page; use its actual schema.
3. Select files on the page first when the tool requires files.
4. Call `run_current_tool` with valid input and settings.
5. Inspect the returned result or error and the displayed output. Retrieve files from the displayed download links.

Calls do not automatically copy or download results. Browser permissions still apply. Interface availability alone is not proof of successful execution.

### Planning specification

Image upload sampling plus manual color entry; clarify color-space and eyedropper support.

This describes intended requirements. Use the implementation notes, interface schema and observed output to determine current support.

### Complete machine-readable capability record

```json
{
  "id": "color-picker",
  "category": "design-tools",
  "built": true,
  "requirements": "Image upload sampling plus manual color entry; clarify color-space and eyedropper support.",
  "implementation": {
    "fields": [
      {
        "key": "color",
        "label": "Color",
        "value": "#3366cc",
        "type": "color"
      }
    ],
    "experience": {
      "automatic": true,
      "single": true,
      "label": "Color value",
      "placeholder": "#3366cc",
      "help": "Enter a hex color or use the color picker. Results update as you type. Up to 1,000,000 characters.",
      "action": null
    },
    "mode": "automatic",
    "interactive": false
  },
  "execution": "POST /api/v1/tools/color-picker/run",
  "api": {
    "id": "color-picker",
    "name": "Color picker",
    "category": "design-tools",
    "description": "Image upload sampling plus manual color entry.",
    "notes": "",
    "human_path": "/en/design-tools/color-picker/",
    "method": "POST",
    "endpoint": "/api/v1/tools/color-picker/run",
    "schema_url": "/api/v1/tools/color-picker",
    "input_schema": {
      "type": "object",
      "additionalProperties": false,
      "properties": {
        "input": {
          "type": "string",
          "maxLength": 1000000,
          "default": "",
          "description": "Plain text input. File tools use files instead unless otherwise documented."
        },
        "options": {
          "type": "object",
          "additionalProperties": false,
          "properties": {
            "color": {
              "type": "string",
              "description": "Color",
              "default": "#3366cc"
            }
          }
        }
      }
    },
    "output_schema": {
      "type": "object",
      "required": [
        "tool",
        "result"
      ],
      "properties": {
        "tool": {
          "type": "string"
        },
        "result": {
          "type": "object",
          "required": [
            "text",
            "files"
          ],
          "properties": {
            "text": {
              "type": [
                "string",
                "null"
              ]
            },
            "data": {
              "description": "Parsed JSON when the textual result is JSON."
            },
            "name": {
              "type": "string"
            },
            "mime": {
              "type": "string"
            },
            "files": {
              "type": "array",
              "items": {
                "type": "object",
                "required": [
                  "name",
                  "mime",
                  "bytes",
                  "base64"
                ],
                "properties": {
                  "name": {
                    "type": "string"
                  },
                  "mime": {
                    "type": "string"
                  },
                  "bytes": {
                    "type": "integer"
                  },
                  "base64": {
                    "type": "string",
                    "contentEncoding": "base64"
                  }
                }
              }
            }
          }
        }
      }
    },
    "processing": "Server; same transformation code as browser tools",
    "limits": {
      "request_bytes": 8388608,
      "input_characters": 1000000,
      "files_bytes": 5242880,
      "max_files": 0,
      "timeout_seconds": 12
    }
  },
  "agent_processing": "Server; same transformation code as browser tools",
  "browser_agent": {
    "supported": true,
    "name": "run_current_tool",
    "discovery": "WebMCP on the human page in a supporting browser",
    "verification": "See audit/API-AUDIT.md; availability is not verification"
  }
}
```

## Page guide

Image upload sampling plus manual color entry.

## Useful next steps

- [Palette generator](https://happytails.ai/en/design-tools/palette-generator/): Generate from image or seed. ([Markdown](https://happytails.ai/en/design-tools/palette-generator.md))

- [Hex to RGB](https://happytails.ai/en/design-tools/hex-to-rgb/): 3/6/8-digit HEX support and explicit alpha interpretation. ([Markdown](https://happytails.ai/en/design-tools/hex-to-rgb.md))

- [Contrast checker](https://happytails.ai/en/design-tools/contrast-checker/): Compute stated WCAG ratio for foreground/background. ([Markdown](https://happytails.ai/en/design-tools/contrast-checker.md))

## How to use Color picker

1. Enter color value in the input field.
2. The result updates as you type. Adjust the available settings if needed.
3. Review the result, then use Copy result or a download link when available.

## Working with color picker

Design utilities help translate colors, dimensions and layout values into reusable settings. A color representation or size calculation is only useful when its units and intended display context are clear.

## Common questions

### Are colors identical on every display?

No. Display calibration, color management and viewing conditions can change appearance. Numeric color conversion does not control those conditions.

### Does a computed contrast ratio describe the whole design?

A ratio compares specified foreground and background colors. Transparency, images, font size and other visual choices can change the actual reading experience.

Continue your workflow: [Palette generator](https://happytails.ai/en/design-tools/palette-generator/), [Hex to RGB](https://happytails.ai/en/design-tools/hex-to-rgb/), [Contrast checker](https://happytails.ai/en/design-tools/contrast-checker/).