Skip to content
ChordChordChord Docs

Meta aggregator

GET /v1/meta/quote and POST /v1/meta/swap are the swap endpoints built for agents: one call on any of the eight EVM chains that ends in a route you can sign, or an honest “no route anywhere”.

Chord’s own router always answers first. A third-party aggregator answers only when Chord fails, and every answer names the provider and the reason.

Chain First Fallbacks, in order
Monad 143 Chord router KyberSwap, Monorail, Relay
Robinhood Chain 4663 Chord router KyberSwap, LI.FI, Relay
Arc 5042 Chord router KyberSwap, LI.FI, Relay
Avalanche 43114 Chord router KyberSwap, LI.FI, Relay
Base 8453 Chord router KyberSwap, LI.FI, Relay
BNB Chain 56 Chord router KyberSwap, LI.FI, Relay
Arbitrum One 42161 Chord router KyberSwap, LI.FI, Relay
Ethereum 1 Chord router KyberSwap, LI.FI, Relay

The live order and each provider’s breaker state: GET /v1/meta/providers.

When a fallback is used

Section titled “When a fallback is used”

Only on a Chord failure:

  • the routing engine timed out, returned an error, or is down (a cold start, a deploy);
  • Chord has no route for the pair or the size;
  • Chord refuses the route itself: the value guard, a taxed token, a stale bonding-curve route;
  • the Chord router is not live on that chain;
  • the transaction Chord built fails simulation.

Never because another aggregator shows a better price. Never on a user error: an address that is not a token, a bad amount or an unknown chain is answered with HTTP 400 and no other provider is asked.

What you get back

Section titled “What you get back”

The same shape whichever provider answered.

Field Meaning
provider chord, kyberswap, monorail, lifi, relay. null = no provider has a route.
fallbackReason null when Chord answered, otherwise why it did not (no_route, engine_timeout, value_guard, simulation_failed, …).
attempts Every provider asked, in order, with status, ms and a short error.
amountOut What the taker receives after every fee, smallest unit.
minAmountOut The minimum the transaction enforces, from the slippage you asked for.
priceImpactPct · valueLossPct Impact when the provider states one; value lost at Chord’s own prices (null when a side has no reliable price).
feeBps · feeRecipient Chord path: Chord’s protocol fee. Fallback: the integrator fee Chord added (0 today); the provider’s own fees are inside amountOut.
route.venues Venue names.
tx {to, data, value, gas, chainId}, unsigned. null without taker.
approval {token, spender, amount} to send first, or null.
simulation The transaction run as the taker: {ok, amountOut, gasUsed}.
safety A security scan of the unknown token, when the value check could not run.
warnings INSUFFICIENT_BALANCE, UNPRICED, OUTPUT_WRAPPED, NO_ROUTE.
quoteId · expiresAt Rebuild with POST /v1/meta/swap {quoteId, taker} within 2 minutes; quote again after expiresAt.

Note the one difference from /v1/quote: its outputAmount is before Chord’s fee, amountOut here is after every fee, so answers from different providers compare directly.

The checks on a fallback answer

Section titled “The checks on a fallback answer”

A third-party answer is untrusted data until it passes all of these. One failure and the next provider is asked.

  1. Allowlist. The transaction target and the approval spender must be that provider’s known router on that chain, and have code there. Anything else is refused, never returned.
  2. Calldata. For KyberSwap the calldata is decoded: receiver, tokens and amount must be what you asked.
  3. Minimum. minAmountOut comes from your slippage. A provider minimum below it is refused.
  4. Value guard. An output worth 30 % less than the input at Chord’s own prices is refused, exactly as on /v1/swap. When Chord has no price for a side, the token is scanned (safety) and a honeypot is refused.
  5. Simulation. With a taker, the transaction is run as that wallet and must deliver at least minAmountOut to it. A fallback transaction that cannot be simulated is never returned.

The simulation runs the swap from the taker’s own address and measures the taker’s balance of the output token before and after, so it means the same thing for every aggregator. When the taker does not hold the input yet, the input is supplied for the simulation and the answer carries INSUFFICIENT_BALANCE.

Quote, then sign

Section titled “Quote, then sign”
Terminal window
# 1. Price (read-only)
curl -s "https://api.getchord.xyz/v1/meta/quote?chain=base&tokenIn=0x833589fcd6edb6e08f4c7c32d4f71b54bda02913&tokenOut=0x4200000000000000000000000000000000000006&amount=10000000&slippageBps=50"


# 2. The unsigned transaction for a wallet (simulated as that wallet)
curl -s -X POST https://api.getchord.xyz/v1/meta/swap -H 'Content-Type: application/json' \
  -d '{"chain":"base","tokenIn":"0x833589fcd6edb6e08f4c7c32d4f71b54bda02913","tokenOut":"0x4200000000000000000000000000000000000006","amount":"10000000","slippageBps":50,"taker":"0xYourWallet"}'

Then, in your own wallet:

  1. If approval is not null, send token.approve(spender, amount) and wait for it.
  2. Sign and send tx on tx.chainId.

Chord never signs and never holds funds.

Reading the status codes

Section titled “Reading the status codes”
Answer Meaning
200, provider set A route. Read provider and fallbackReason first.
200, provider: null Every provider looked and none has a route.
400 Your request: INVALID_PARAMS, UNSUPPORTED_CHAIN, UNKNOWN_TOKEN.
404 on /meta/swap NO_ROUTE, with attempts.
410 on /meta/swap QUOTE_EXPIRED: send the full params.
503 UNAVAILABLE Nobody could answer right now (timeouts, an open breaker). Retry in a few seconds; this is not “no route”.

For agents

Section titled “For agents”
  • MCP and function calling: chord_quote and chord_swap_tx call this endpoint on every EVM chain (MCP server, tools manifest).
  • The Agent Skill quotes through the meta aggregator first and checks the router of every answer against its own pinned list.
  • Solana is not on this endpoint: Solana swaps are /v1/sol/trade/*, where every quote builds Chord’s own Solana route and Jupiter’s for the wallet and keeps the better one. See Solana.