Been heads down building. Quick update for anyone working in the agentic payments space.
PQS (Prompt Quality Score), the pre-flight quality gate for AI agent workflows, now accepts x402 payments on both Base mainnet and Solana, in addition to the existing free tier and API key access.
What PQS does
Before your agent sends a prompt to an expensive LLM endpoint, PQS scores it across 8 dimensions: clarity, specificity, context, constraints, output format, role definition, examples, and chain-of-thought structure. Returns a score 0–80, grade A–F, percentile ranking, and top 3 fixes.
Catch weak prompts before they cost you tokens or USDC.
Endpoint reference
Free tier — no auth required**
POST https://pqs.onchainintel.net/api/score/free
{ "prompt": "your prompt here", "vertical": "software" }
Score + dimensional breakdown — $0.025 USDC via x402
POST https://pqs.onchainintel.net/api/score
Full analysis + optimized rewrite — $0.125 USDC via x402
POST https://pqs.onchainintel.net/api/score/full
Batch up to 5 prompts — $0.25 USDC via x402
POST https://pqs.onchainintel.net/api/score/batch
A/B compare two prompts — $1.25 USDC via x402
POST https://pqs.onchainintel.net/api/score/compare
x402 payment details
Base mainnet: CDP facilitator, USDC ERC-20, EIP-3009 TransferWithAuthorization
Solana: x402-compatible, USDC SPL token
No account required for x402 path — agent pays per call, no subscription
API key path also available for subscription-based access
- MCP server bash npx pqs-mcp-server
- Listed on Smithery (88/100),
- Official MCP Registry, Glama, and mcp.so.
- Three tools: score_prompt (free), optimize_prompt ($0.025), compare_models ($1.25).
- Python SDK
- bash pip install pqs-sdk
- Async support via AsyncPQSClient.
- Full x402 and API key auth. OpenAPI spec:
https://pqs.onchainintel.net/openapi.json
Building this as infrastructure for the agent economy, score the input before the inference fires. Cheaper than one bad prompt.
@kenburbary| pqs.onchainintel.net