A side-by-side look at the Ai Model Experiments and Pqs MCP Server MCP servers: transport, auth, tools, quality signals, and the config to install either one in Claude, Cursor, Windsurf or VS Code.
Verdict: choose Ai Model Experiments for conversational ai work as a local process; choose Pqs MCP Server for conversational ai as a local process. You can also run both side by side in one mcpServers block.
experiment_models, experiment_estimate, experiment_create.PQS_BASE.score_prompt, optimize_prompt.Rows where the two servers differ are marked.
| Spec | ||
|---|---|---|
| Category | Conversational AI | Conversational AI |
| Quality signal | 61/100 · Good | 56/100 · Good |
| Install command | Confirmed | Confirmed |
| Transport | Local subprocess (stdio) | Local subprocess (stdio) |
| Auth | Not declared | Not declared |
| Pricing | Not declared | Not declared |
| Required env vars | None listed | PQS_BASE |
| Verified owner | Community listing | Community listing |
| GitHub stars | 0 | 2 |
| Directory activity | 1 views 0 installs 0 upvotes | 2 views 0 installs 0 upvotes |
| Tools | 8 | 2 |
| Full listing | View Ai Model Experiments | View Pqs MCP Server |
experiment_modelsList AI models available for experiments (about 300 across Anthropic, OpenAI, Google, Meta, Mistral, DeepSeek, Qwen and more), with context window and OUR per-token prices (provider cost × 1.5 — what experiments actually bill). Filter by name/vendor search, minimum context, or max price. Use the returned model ids in experiment_create. Example: experiment_models({ search: "claude", min_context: 100000 })experiment_estimateDry-run cost estimate for an experiment BEFORE creating it — cell count and estimated billed cost range (at our 1.5× pricing) for prompts × models × reps. Free to call, no side effects, does not need credit balance. Same spec shape as experiment_create. Example: experiment_estimate({ prompts: ["Summarize: ..."], models: ["anthropic/claude-sonnet-4.5", "openai/gpt-5"], reps: 2 })experiment_createModel Lab: run one prompt across many AI models at once and compare their outputs, cost, and latency side by side. Create and start an experiment: run each prompt against each model (× reps), collecting output, tokens, latency, and billed cost per cell. PREPAID: requires Pipeworx credit balance ≥ max_spend_usd (top up via experiment_topup); bills actual provider cost × 1.5 with a $0.10 minimum per experiment. ASYNC: returns experiment_id immediately — execution starts within ~1 minute; poll experiment_status until complete, then call experiment_results. Do NOT wait synchronously. Set summary:false to skip the AI-written model-comparison summary. Example: experiment_create({ name: "tone test", prompts: ["Rewrite formally: ..."], models: ["anthropic/claude-haiku-4.5", "openai/gpt-5-mini"], reps: 2, max_spend_usd: 2 })experiment_statusProgress of an experiment: cell counts by state (pending/running/ok/error/skipped), spend so far vs cap, and whether it is complete. Poll this after experiment_create (every few seconds). Example: experiment_status({ experiment_id: "..." })experiment_resultsResults of an experiment: per-model aggregates (mean latency, tokens, total billed cost, error rate), per-cell outputs, and the AI-written summary comparing how the models differed (if enabled). Use include_outputs:false for aggregates only. Example: experiment_results({ experiment_id: "..." })experiment_listList your experiments, newest first, with status and spend. Example: experiment_list({ limit: 10 })experiment_cancelCancel a running experiment: pending cells are skipped (not billed); in-flight cells finish and bill. Example: experiment_cancel({ experiment_id: "..." })experiment_topupHow to add prepaid credits for experiments (and your current balance). Payment is x402 — USDC on Base, paid in-band by any wallet-equipped agent: POST https://gateway.pipeworx.io/credits/topup?amount_usd=10 responds HTTP 402 with payment requirements; retry with PAYMENT-SIGNATURE to settle and the credits land instantly. Example: experiment_topup({})score_promptScore a prompt's quality across 8 dimensions BEFORE sending it to an expensive
model. Returns a 0-80 score, an A-F grade, the per-dimension breakdown
(clarity, specificity, context, constraints, output_format, role_definition,
examples, cot_structure), and the weakest dimension.
USE WHEN:
- The user is workshopping a prompt and asks "is this good?" / "will this
work?" / "should I add more detail?"
- The user is about to send a long or expensive prompt to GPT-4, Claude Opus,
or any frontier model, especially in a batch or automation context where
rework is costly.
- The user mentions iterating on a prompt that produced poor output and wants
to diagnose what's missing.
- The user pastes a prompt and asks for feedback on it.
DO NOT USE WHEN:
- The user is asking you to write a prompt for them (write it yourself first,
then optionally call score_prompt to verify).
- The prompt is conversational chat (this scores task-shaped prompts).
COST: Free, no API key required. Rate-limited per IP: 5/min, 10/day, 100/month.
If the user exceeds the limit, the response will include a structured upgrade
path with subscribe and account URLs.
LATENCY: ~2 seconds.optimize_promptRewrite a prompt to score higher on the PQS rubric, AND show before/after
output comparisons so the user can see the impact. Returns the optimized
prompt, the original PQS score, the optimized PQS score, and side-by-side
sample outputs from a frontier model using both versions.
USE WHEN:
- The user got a low score from score_prompt and asks how to improve.
- The user explicitly asks to "improve" / "rewrite" / "fix" / "optimize" a
prompt they pasted.
- The user is dissatisfied with output quality from a previous prompt and
asks how to get better results.
- score_prompt returned a suggestion to invoke this tool.
DO NOT USE WHEN:
- The user just asked for a score (use score_prompt only — don't double up).
- The user wants you to write a new prompt from scratch (write it directly).
REQUIRES: A PQS API key from a Pro subscription ($19.99/month, 1,000 calls/mo,
includes batch + A/B comparison). If the user has not provided one, the tool
returns a clear subscription URL — pass that response to the user verbatim.
Do not invent or guess API keys. There is no free trial of this tool; the
user must subscribe before the first call.
COST: Counted against your Pro subscription's monthly call quota.
LATENCY: ~6-8 seconds.Paste either block (or both) into your client config, e.g. claude_desktop_config.json or ~/.cursor/mcp.json. We only show a config when the install command is confirmed.
{
"mcpServers": {
"ai-model-experiments": {
"command": "npx",
"args": [
"-y",
"@pipeworx/mcp-ai-model-experiments"
]
}
}
}
{
"mcpServers": {
"pqs-mcp-server": {
"command": "npx",
"args": [
"-y",
"pqs-mcp-server"
],
"env": {
"PQS_BASE": "YOUR_PQS_BASE_HERE"
}
}
}
}