Color Similarity for AI Agents
The tool
Color Similarity Calculator provides detailed color comparison using both RGB and HSL color spaces, calculating similarity percentages, color distances, and providing categorical similarity ratings.
Once your client is connected to the VerveContext MCP server, this appears in its tool list as ColorSimilarityforAIAgents. It is read-only and open-world: it fetches, it never mutates anything on your side, so most clients will call it without asking you to confirm.
{
"name": "ColorSimilarityforAIAgents",
"arguments": {
"color1": "FF5733",
"color2": "FF6B47"
}
}What that looks like in a conversation
You don't name the tool — the model picks it. Asking about FF5733 in the terms this source covers is enough for it to reach for ColorSimilarityforAIAgents on its own.
Connecting
One server URL covers every source in the catalog, including this one. Authorization is OAuth — the client opens a browser once and there is no key to paste into a config file.
{
"mcpServers": {
"vervecontext": {
"url": "https://api.vervecontext.com/v1/mcp"
}
}
}https://api.vervecontext.com/v1/mcpPer-client setup — Claude Desktop, Cursor, VS Code, ChatGPT — is on the MCP setup page.
Arguments
These are the properties on the tool's inputSchema, so a well-behaved client validates them before the call is made.
| Argument | Type | Example | Description |
|---|---|---|---|
color1Required | string | FF5733 | First hex color value (with or without # prefix) |
color2Required | string | FF6B47 | Second hex color value (with or without # prefix) |
What the model gets back
The result carries a structuredContent object matching the tool's declared outputSchema, so a client can read fields without parsing prose. status is "ok" on success and error is null; a null field means the value wasn't available for that input, not that the call failed.
{
"status": "ok",
"error": null,
"data": {
"color1": {
"hex": "#FF5733",
"rgb": {
"r": 255,
"g": 87,
"b": 51
},
"hsl": {
"h": 10.6,
"s": 100,
"l": 60
}
},
"color2": {
"hex": "#FF6B47",
"rgb": {
"r": 255,
"g": 107,
"b": 71
},
"hsl": {
"h": 11.7,
"s": 100,
"l": 63.9
}
},
"rgb_distance": 28.28,
"rgb_similarity": 93.6,
"hsl_similarity": 97.71,
"overall_similarity": 95.65,
"delta_e": 28.28,
"hue_difference": 1.15,
"saturation_difference": 0,
"lightness_difference": 3.92,
"similarity_category": "nearly identical",
"are_identical": false
}
}Fields
| Field | Type | Example | Description |
|---|---|---|---|
color1 | object | The first colour, in hex, RGB and HSL | |
└ color1.hex | string | First color in hexadecimal format representation | |
└ color1.rgb | object | First colour as red, green and blue channels | |
└ color1.rgb.r | number | Red channel value for first color | |
└ color1.rgb.g | number | Green channel value for first color | |
└ color1.rgb.b | number | Blue channel value for first color | |
└ color1.hsl | object | First colour as hue, saturation and lightness | |
└ color1.hsl.h | number | Hue value for first color in degrees | |
└ color1.hsl.s | number | Saturation percentage for first color | |
└ color1.hsl.l | number | Lightness percentage for first color | |
color2 | object | The second colour, in hex, RGB and HSL | |
└ color2.hex | string | Second color in hexadecimal format representation | |
└ color2.rgb | object | Second colour as red, green and blue channels | |
└ color2.rgb.r | number | Red channel value for second color | |
└ color2.rgb.g | number | Green channel value for second color | |
└ color2.rgb.b | number | Blue channel value for second color | |
└ color2.hsl | object | Second colour as hue, saturation and lightness | |
└ color2.hsl.h | number | Hue value for second color in degrees | |
└ color2.hsl.s | number | Saturation percentage for second color | |
└ color2.hsl.l | number | Lightness percentage for second color | |
rgb_distancePremium | number | Euclidean distance between colors in RGB space | |
rgb_similarityPremium | number | Percentage similarity based on RGB color space | |
hsl_similarityPremium | number | Percentage similarity based on HSL color space | |
overall_similarity | number | Combined similarity percentage from all algorithms | |
delta_ePremium | number | Delta E color difference metric for perceptual similarity | |
hue_differencePremium | number | Hue difference between colors in degrees | |
saturation_differencePremium | number | Saturation percentage difference between colors | |
lightness_differencePremium | number | Lightness percentage difference between colors | |
similarity_category | string | Human readable category describing similarity level | |
are_identical | boolean | Boolean indicating if colors are exactly identical |
Why ground on it
A model can produce something that looks like this answer from its training data, and be confidently out of date or simply wrong. This source returns the current value with a shape you can check, which is the difference between an answer you can cite and one you have to hedge.
Point an evaluation at overall_similarity: it is the field most worth pinning a claim to, and it is either present and current or absent — never plausibly invented.
Failure modes
Errors come back as tool errors with a sentence the model can act on, not a bare status code.
| Status | What it means |
|---|---|
400 / 422 | The arguments didn't validate. The message names the offending one. |
401 | The OAuth session is invalid or expired — reconnect the server. |
403 | Out of credits. Not a bad key — the month's allowance is spent. |
404 | This source isn't part of VerveContext. Check the catalog. |
429 | Brief rate limit. Retrying after a moment succeeds. |
Other ways to use Color Similarity for AI Agents
Set up Color Similarity for AI Agents on VerveContext, or reach the same source a different way. Your VerveContext account and credits work on all of them — one key, one balance.
Frequently asked questions
Do I have to tell the agent to use ColorSimilarityforAIAgents?
No. The tool's name and description are in the model's context once the server is connected, so it selects the tool when the question calls for it. Naming it explicitly works too and is useful when you want to force the call.
Does connecting the server expose every tool at once?
Yes — one connection lists the whole VerveContext catalog. Clients with a tool budget can usually filter the list; the credit cost is per call, so an unused tool costs nothing.
What does a call cost?
1 credit each time the tool actually runs. A model that reasons about the tool without calling it costs nothing.
Is there a REST version of this?
Yes — the same source is available as a plain HTTPS endpoint on APIVerve, linked above. Same data, same credits, same account.