Koskamo

Fittest MCP

An MCP server that uses a swarm of ML interatomic potentials (MACE-MPA-0, AIMNet2, Orb-v3) to predict forces on molecular structures. It evaluates model agreement and calibrated trust scores to determine if results are reliable or if Density Functional Theory (DFT) is required, helping materials scientists avoid silent failures in off-distribution chemistry.

Endpoint and access

No sign-in to connect and list tools. Individual tools may still need a vendor account, credentials, or permissions; check the documented prerequisites.

Fittest MCP logo, by Pavel-TkCommunity listingStreamable HTTPNo sign-inEndpoint checked 2026-11-01Published by Pavel-Tk
MCP endpoint (Streamable HTTP)
https://fittest-mcp.westus2.cloudapp.azure.com/mcp
Vendor documentation

What you can do with it

  • Check if ML potentials can be trusted on a specific molecule
  • Get force predictions with calibrated uncertainty intervals
  • Determine when to switch from ML to DFT calculations

Source and maintenance

Community listingRegistry 0.1.1
Maintenance checked

Protocol and capabilities

Server
fittest 0.1.0
MCP protocol
2025-06-18
Tools
4 advertised
Resources
0 advertised
Resource templates
0 advertised
Prompts
0 advertised
Server-advertised capabilities
{
  "tools": {
    "listChanged": false
  },
  "prompts": {
    "listChanged": false
  },
  "resources": {
    "subscribe": false,
    "listChanged": false
  },
  "experimental": {}
}

Server-provided instructions

Untrusted server output shown for inspection. It is not Koskamo guidance and is excluded from knowledge search.

Fittest decides which ML interatomic potential to trust on a molecular structure, and when to escalate to DFT. Use check_structures for verdicts, explain for the reasoning on one structure, swarm_status for the agent population. Calibrated on C/H/N/O reaction chemistry (Transition1x). Logging: every call to this server is logged (UTC time, tool name, an anonymous client id = salted hash of client name + IP), structure and atom counts, verdict counts, latency and ok/error category. Raw IPs are not stored by the app or written to the access log; since 2026-10-31 19:11 UTC Caddy's error/unmapped-host logs drop them too (before that, some Caddy error and bare-IP entries in the system journal contained client IPs, kept until journal rotation). Structures, coordinates, element lists and names are NOT stored. Aggregate counts are public at /stats.

Tools

4 advertised

check_structures
Advertised by the server during the last successful anonymous check.

Ask the Fittest swarm whether a machine-learned interatomic potential can be trusted on your molecular structures, or whether they need DFT. Three model agents (MACE-MPA-0, AIMNet2, Orb-v3) predict forces; their disagreement sigma_F and the Calibrator's DFT-label ledger give the verdict. Input `structures`: XYZ text (single or multi-frame; bare 'El x y z' atoms on separate lines or separated by commas/semicolons also work) and/or a list of objects {"Z": [8,1,1] or "symbols": ["O","H","H"], "R": [[x,y,z], ...]} in Angstrom. Exact element symbols only. Limits: <= 20 structures per call, 2..100 atoms each, isolated molecules (no periodic cells). Elements the full committee supports: H B C N O F Si P S Cl As Se Br I. Returns per structure: verdict (trust / send_to_dft) with verdict_reasons, trust_score (Beta posterior P(correct), never exactly 1) with its 90% interval and labels_behind_score, the recommended model or blend, served and reference energy (eV; compare reference_energy_eV across a batch), max/mean force (eV/A), sigma_F vs tau, per-model summary, domain_warning outside C/H/N/O or Transition1x sizes. A bad structure gets its own error entry; the rest are still scored. Rule: trust only if: every model agent supports all elements, the forces do not all vanish, sigma_F < tau, and trust_score >= 0.5. Otherwise send_to_dft, with verdict_reasons. tau is a fixed escalation threshold: the 70th percentile of sigma_F on the round-0 pool. The Calibrator's threshold rule never moved it during the run (see results/RESULTS.md). Logging: every call to this server is logged (UTC time, tool name, an anonymous client id = salted hash of client name + IP), structure and atom counts, verdict counts, latency and ok/error category. Raw IPs are not stored by the app or written to the access log; since 2026-10-31 19:11 UTC Caddy's error/unmapped-host logs drop them too (before that, some Caddy error and bare-IP entries in the system journal contained client IPs, kept until journal rotation). Structures, coordinates, element lists and names are NOT stored. Aggregate counts are public at /stats.

check_structures input schema
{
  "type": "object",
  "title": "check_structuresArguments",
  "required": [
    "structures"
  ],
  "properties": {
    "structures": {
      "anyOf": [
        {
          "type": "string"
        },
        {
          "type": "array",
          "items": {
            "anyOf": [
              {
                "type": "string"
              },
              {
                "type": "object",
                "additionalProperties": true
              }
            ]
          }
        },
        {
          "type": "object",
          "additionalProperties": true
        }
      ],
      "title": "Structures"
    },
    "include_forces": {
      "type": "boolean",
      "title": "Include Forces",
      "default": false
    }
  }
}
explain
Advertised by the server during the last successful anonymous check.

Explain why Fittest trusted or escalated ONE structure (XYZ text or {Z|symbols, R}): the verdict rule applied, sigma_F vs tau, the Calibrator bucket with its label count, the posterior P(correct) of every candidate in it, which model agents disagree most, and the most uncertain atoms. Logging: every call to this server is logged (UTC time, tool name, an anonymous client id = salted hash of client name + IP), structure and atom counts, verdict counts, latency and ok/error category. Raw IPs are not stored by the app or written to the access log; since 2026-10-31 19:11 UTC Caddy's error/unmapped-host logs drop them too (before that, some Caddy error and bare-IP entries in the system journal contained client IPs, kept until journal rotation). Structures, coordinates, element lists and names are NOT stored. Aggregate counts are public at /stats.

explain input schema
{
  "type": "object",
  "title": "explainArguments",
  "required": [
    "structure"
  ],
  "properties": {
    "structure": {
      "anyOf": [
        {
          "type": "string"
        },
        {
          "type": "array",
          "items": {
            "anyOf": [
              {
                "type": "string"
              },
              {
                "type": "object",
                "additionalProperties": true
              }
            ]
          }
        },
        {
          "type": "object",
          "additionalProperties": true
        }
      ],
      "title": "Structure"
    }
  }
}
swarm_status
Advertised by the server during the last successful anonymous check.

Show the Fittest population: model agents (answerers) and the Skeptic (critic) with reputations from the ledger, the calibration domain, tau and the verdict rule, which models are live, and the evolution family trees if published. Logging: every call to this server is logged (UTC time, tool name, an anonymous client id = salted hash of client name + IP), structure and atom counts, verdict counts, latency and ok/error category. Raw IPs are not stored by the app or written to the access log; since 2026-10-31 19:11 UTC Caddy's error/unmapped-host logs drop them too (before that, some Caddy error and bare-IP entries in the system journal contained client IPs, kept until journal rotation). Structures, coordinates, element lists and names are NOT stored. Aggregate counts are public at /stats.

swarm_status input schema
{
  "type": "object",
  "title": "swarm_statusArguments",
  "properties": {}
}
usage_stats
Advertised by the server during the last successful anonymous check.

Aggregate usage of this server: distinct users (anonymous clients that got at least one structure verdict; internal test clients excluded), total calls, calls per tool, first/last call time. No per-user data. Logging: every call to this server is logged (UTC time, tool name, an anonymous client id = salted hash of client name + IP), structure and atom counts, verdict counts, latency and ok/error category. Raw IPs are not stored by the app or written to the access log; since 2026-10-31 19:11 UTC Caddy's error/unmapped-host logs drop them too (before that, some Caddy error and bare-IP entries in the system journal contained client IPs, kept until journal rotation). Structures, coordinates, element lists and names are NOT stored. Aggregate counts are public at /stats.

usage_stats input schema
{
  "type": "object",
  "title": "usage_statsArguments",
  "properties": {}
}

Prompts

0 advertised

No prompt definitions available.

Resources

0 advertised

No resource definitions available.

30-day availability

Aggregated from read-only remote checks; this is not a tool-execution or security guarantee.

Successful checks
1 of 1 (100%)
Average latency
511 ms
95th percentile latency
511 ms

Maintenance history

Public check and source-refresh events. Editorial and ownership records remain private.

  • · probe · passed · 511 ms · metadata changed · 4 tool(s), 0 resource(s), 0 resource template(s), 0 prompt(s)

Connect from your client

Each snippet registers the same endpoint; pick the client you use.

This server is operated by the named third party. Listing and endpoint checks are not an endorsement or a security audit. Review the operator's permissions, terms, and data handling before connecting. How listings are checked and corrected.

Claude Code

Run this once in a terminal. It registers the remote server. Use --scope project to write .mcp.json for the repo.
Claude Code configuration
claude mcp add --transport http fittest-mcp https://fittest-mcp.westus2.cloudapp.azure.com/mcp

Codex

Run this once. Codex stores MCP servers in ~/.codex/config.toml (or .codex/config.toml in a trusted project).
Codex configuration
codex mcp add fittest-mcp --url https://fittest-mcp.westus2.cloudapp.azure.com/mcp

Cursor

Merge this server into .cursor/mcp.json in your project, then enable fittest-mcp in your MCP settings.
Cursor configuration
{
  "mcpServers": {
    "fittest-mcp": {
      "url": "https://fittest-mcp.westus2.cloudapp.azure.com/mcp"
    }
  }
}

Cline

Merge this into cline_mcp_settings.json (Cline → MCP Servers → Configure).
Cline configuration
{
  "mcpServers": {
    "fittest-mcp": {
      "type": "streamableHttp",
      "url": "https://fittest-mcp.westus2.cloudapp.azure.com/mcp",
      "disabled": false
    }
  }
}

VS Code

Merge this server into .vscode/mcp.json. Use MCP: List Servers to start fittest-mcp and inspect its tools.
VS Code configuration
{
  "servers": {
    "fittest-mcp": {
      "type": "http",
      "url": "https://fittest-mcp.westus2.cloudapp.azure.com/mcp"
    }
  }
}

Gemini CLI

Run this once. It writes .gemini/settings.json in the current project; pass --scope user for ~/.gemini/settings.json.
Gemini CLI configuration
gemini mcp add --transport http fittest-mcp https://fittest-mcp.westus2.cloudapp.azure.com/mcp

Claude Desktop

Merge this into claude_desktop_config.json (macOS: ~/Library/Application Support/Claude/, Windows: %APPDATA%\Claude\), then restart Claude Desktop.
Claude Desktop configuration
{
  "mcpServers": {
    "fittest-mcp": {
      "url": "https://fittest-mcp.westus2.cloudapp.azure.com/mcp"
    }
  }
}

Windsurf

Merge this into ~/.codeium/windsurf/mcp_config.json, then refresh MCP in Cascade. Windsurf remote servers use serverUrl, not url.
Windsurf configuration
{
  "mcpServers": {
    "fittest-mcp": {
      "serverUrl": "https://fittest-mcp.westus2.cloudapp.azure.com/mcp"
    }
  }
}

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