Chess position evaluation and tactical puzzle API.

Analyze FEN positions, query verified single-solution tactical puzzles by motif, and run batch PGN game reviews over HTTP.

API Reference Python SDK
POST /v1/evaluate
+0.24
Evaluation
+0.24 (53.4%)
Search Telemetry
d24 · 1.84M
Motif & Audit
center_control
Tip: Click any piece on the board to make a legal move and evaluate the resulting position live.
FEN

Core endpoints

Three HTTP endpoints for position analysis, tactical puzzle queries, and PGN game review.

POST /v1/evaluate

Position Evaluation

Pass a FEN string and optional candidate move to retrieve centipawn scores, win/draw/loss probabilities, principal variations, and move commentary.

GET /v1/puzzles

Tactical Puzzle Feed

Filter single-solution tactical positions by motif tag and rating range. Every position is checked to ensure only one winning move exists.

POST /v1/reports

Batch PGN Review

Submit PGN game strings to identify blunders, missed tactics, and accuracy breakdowns across opening, middlegame, and endgame phases.

Endpoint Description Typical Response Fields Returned
POST /v1/evaluate Position evaluation and Multi-PV lines ~18 ms eval_cp, wdl, best_move, pv, coaching_summary
GET /v1/puzzles Tactical and mating pattern query ~7 ms puzzle_id, fen, best_move, motif, difficulty_elo
POST /v1/reports PGN game accuracy and blunder log ~340 ms / game accuracy, critical_moments, missed_tactics

Quickstart

Use the Python client or standard HTTP requests. Test tokens are rate-limited to 100 requests per hour.

Test Token

Use this token for local testing or generate a new one below.

Rate limit: 100 req/hr · Endpoint: plyvero-api.somer-5b7.workers.dev
Test Live Endpoint Ready
from plyvero import PlyveroClient

client = PlyveroClient(api_key="ply_sbx_live_94a8f10c3e7b2d4190a2")

# Evaluate a position
analysis = client.evaluate(
    fen="r1bqk2r/pppp1ppp/2n2n2/2b1p3/2B1P3/5N2/PPPP1PPP/RNBQK2R w KQkq - 4 4",
    played_move="d2d3",
    multipv=3,
    include_coaching=True
)
print(analysis.eval_cp, analysis.coaching_summary)

# Fetch tactical puzzles by motif
puzzles = client.puzzles.query(
    motif="back_rank_deflection",
    rating_min=1900,
    rating_max=2250,
    limit=5
)

Pricing

Monthly plans based on evaluation volume.

Starter

For personal projects and testing.

$0 / mo
  • 500 position evaluations / month
  • Tactical puzzle query access
  • Web analysis board

Platform

For chess websites and apps.

$99 / mo
  • 250,000 API calls / month
  • Full puzzle and mating pattern feed
  • Dedicated worker queue
  • Webhook batch processing

About

Plyvero Labs is an independent software project built by Saksham Omer, focused on chess position evaluation, curated tactical datasets, and automated game review tools.

Infrastructure

Evaluation requests are processed by stateless Linux worker containers backed by object storage for PGN archives and low-latency REST endpoints.

Contact

Maintainer: Saksham Omer
Email: Somer@student.gitam.edu
GitHub: github.com/somer-eng