Nansen Copytrader Overlay

Nansen is a data layer only in this skill: PM PnL quality overlay + address-summary/wallet quality. It is not smart-money-labeled copytrading — Nansen's smart-money labels are not Polymarket-specific, and no code path here calls the labels endpoint at all.

When to use this skill

Simmer is about to execute a copytrading rebalance into a specific Polymarket market and has a candidate leader list (wallets + an existing wallet_score). Use this skill to re-rank that list using Nansen's Polymarket-specific PnL data before Simmer acts on it.

Do not use this skill to:

• Generate smart-money labels or entity classifications (out of scope — see framing above).
• Place trades. Every function and CLI command here is signal-only; the caller (Simmer's execution wrapper) owns the actual --live gate.

Core signal: pnl-by-market first

The primary ranking signal is pnl_by_market(market_id) — who is actually profitable in the target market, not a wallet's broad trading history. pnl_by_address / trades_by_address (broad history) and address_summary (cheap wallet-quality pre-filter) are secondary — they refine the market-specific score, they never replace it. A wallet absent from the target market's leaderboard gets tagged NOT_IN_MARKET_LEADERBOARD and keeps its original score with a small discount, rather than a fabricated 50/50 blend against a signal that doesn't exist.

Running it

python3 -m venv .venv && source .venv/bin/activate
pip install pytest   # for tests only; the skill itself is stdlib-only
export NANSEN_API_KEY=...   # your own Nansen key — sent as the `apiKey` header

No nansen CLI required: calls go straight to https://api.nansen.ai/api/v1 over HTTPS. Bring-your-own-key — every call spends your Nansen credits, so --max-wallets (default 30) and --max-credits (default 45) are deliberately conservative.

Getting a Nansen key

Sign up at nsn.ai/simmer, then copy your key from the Nansen dashboard. Signing up through that link gets you the Simmer partner discount on your subscription and API credits.

What a run costs. Credit prices measured directly against the live API on 2026-08-11:

At the default caps a full run costs about 45 credits. Note that Nansen's published price list currently shows pnl-by-market at 1 credit; we are billed 5, so budget from the table above rather than from their docs.

Which plan you need. Nansen's free tier gives 100 starter credits plus 10 per day, which covers roughly two full runs and is enough to try the skill. For regular use, Pro (2,000 credits per month) covers about 45 runs. Check your balance any time with GET /api/v1/account, which is free.

Rank leaders for a market:

python3 nansen_skill_cli.py copytrader-overlay \
    --market-id 12345 \
    --leaders leaders.json \
    --top-n 5

leaders.json:

[
  {"proxy_address": "0xabc...", "owner_address": "0xowner...", "wallet_score": 0.8}
]

World Cup market variant (adds WC-specialist bonus to the secondary signal):

python3 nansen_skill_cli.py copytrader-overlay \
    --market-id 12345 --leaders leaders.json --worldcup

Experimental live insider scan (always dry-run — see below):

python3 nansen_skill_cli.py insider-scan --market-id 12345 67890

Programmatic use (what copytrading_strategy.py would actually call):

from nansen_copytrader_overlay_general import enrich_leaders

enriched = enrich_leaders(
    leaders=raw_leaders,           # [{proxy_address, owner_address, wallet_score}, ...]
    market_id=target_market_id,    # the market Simmer is about to copytrade into
    dry_run=not is_live,
)
target_wallets = [l["proxy_address"] for l in enriched[:top_n]]

Proxy vs. owner wallets — must be explicit

Nansen indexes Polymarket activity (prediction-market/...) by the proxy wallet (the contract Polymarket trades through), and profiler data (profiler/...) by the owner (signing/EOA) wallet. address-summary is a prediction-market endpoint, so it takes the proxy — passing the owner returns an all-zero row.

owner_address is optional on input: it rides along on every pnl-by-market row and is read from there when omitted. That harvest covers only about 40% of the leaderboard — 30 of 50 rows on the market used to verify this carried the placeholder "0x" rather than a real owner, which is treated as absent.

A leader missing proxy_address is tagged MISSING_PROXY_ADDRESS and skipped (kept at its original score, discounted).

A leader whose market position has no usable cost basis — none at all (airdropped/gifted) or dust under $10 — is tagged NO_COST_BASIS / DUST_COST_BASIS and its ROI component contributes zero rather than a flat stand-in. It keeps its profit/loss tag and stays eligible for the leaderboard-rank bonus (realised PnL rank is real evidence). Rationale: the typical measured ROI score is ~0.09, so any generous default for an uncomputable ROI would rank the wallets we know least about above the ones we measured. Missing owner_address is tagged MISSING_OWNER_ADDRESS for the record but does not gate the secondary signal — every call in that path is proxy-keyed.

Measured leaders always rank above unmeasured ones

Each returned leader carries nansen_measured. Leaders with a usable Nansen signal are ranked as one block above every leader without one; within each block the order is by adjusted_score.

This matters whenever your leader list is longer than max_wallets, or when some lookups fail. The two scores are not on the same scale — an unmeasured leader keeps base * 0.9, a measured one gets 0.5*base + 0.5*quality, which only exceeds 0.9 when quality is above 0.8. Ranking them together would promote wallets the overlay could not evaluate above nearly every wallet it did, which is the opposite of the point.

If every leader is measured (the intended use), ranking is purely by adjusted_score and this rule changes nothing.

Credit guards (hard, not advisory)

Nansen bills per call against your key, so every enrichment run is protected by:

• max_wallets (default 30): leaders beyond the cap are never enriched — they keep their original score, tagged CREDIT_GUARD_MAX_WALLETS, and are ranked below every leader that was measured (see below).
• CreditGuard(max_credits=...) (default 45): a hard ceiling on the credits spent across the whole run, with a 5-minute TTL cache so re-fetching the same market/wallet doesn't double-spend. It charges the real per-endpoint cost (5 for pnl-by-market and top-holders, 1 for the rest), not one unit per call, so the number means what you think it means. If the budget runs out mid-run, remaining leaders are tagged CREDIT_GUARD_EXHAUSTED and kept at their original score — the run does not crash, and it does not keep spending.
• Preflight balance check: before spending anything, the CLI calls the free account() endpoint. If your balance can't cover even the primary pnl-by-market call it refuses outright; if your balance is below the budget it warns and proceeds, since the budget is a cap rather than a prediction and most runs spend well under it. A failed balance check never blocks the run.
• No profiler labels wrapper exists, so nothing here can call it (100 credits for common labels, 500 for premium). The live insider scan's known-entity discount uses a free local allowlist instead.
• address_summary as a pre-filter: a wallet only gets the more expensive pnl_by_address + trades_by_address pull if its cheap address_summary win-rate/resolved-count check clears MIN_RESOLVED_MARKETS first.

Tune both via the CLI (--max-wallets, --max-credits) or by passing max_wallets= / guard=CreditGuard(max_credits=...) directly.

Live insider scan — experimental, dry-run only

nansen_live_insider_scan.py / insider-scan is not launchable for live trading. scan_live_markets(dry_run=False) and --live both hard-refuse (LiveTradingNotSupportedError), because two things are unconfirmed against the live API:

1. Owner/proxy handling: scanned wallets come from PM trade data (proxy addresses), but historical_balances is a profiler/owner-indexed endpoint — wallet_age_days may be silently wrong until there's an owner mapping for scanned wallets.
2. HIGH_NO_ENTRY price semantics: whether Nansen quotes NO-side trades in YES terms or the NO token's own price changes whether this flag means conviction or the opposite. Unconfirmed — see the module docstring.

Removing the guard requires a deliberate code change after both are verified — not a flag flip.

Tests

source .venv/bin/activate
pytest tests/ -v

Status

This skill ships as research tooling, not an allocation signal. The scoring weights (the 50/50 blend, MIN_RESOLVED_MARKETS, the tag penalties) are reasoned defaults. They have not been fitted or backtested, and no forward test has shown that the re-ranking improves realised copytrading returns. Read DISCLAIMER.md before acting on the output.

Credits

Built by Alyna Takahashi (@alyna123t), who wrote the adapter, both overlays and the insider scan. Code review by Nick (@BridgeAISocial). Published and maintained by Simmer. Nansen provides the underlying Polymarket data.