Swapping Tokens

How Swapping Works

Seashail's swap_tokens tool handles routing automatically:

On Solana: routes through Jupiter aggregator
On EVM chains: routes through Uniswap by default; 1inch available when configured
Policy evaluation happens before signing — swaps are subject to the same tiered approval as any write operation

See Policy and Approvals for how tiered approval works.

Choosing Your Chain

Swaps are chain-specific: you must specify which chain the swap executes on.

Solana swaps use Jupiter (best-route aggregation across Raydium, Orca, etc.)
EVM swaps default to Uniswap; 1inch is available on chains where configured (check get_capabilities)
Cross-chain swaps are NOT supported by swap_tokens — use bridge_tokens first, then swap on the destination chain

See Chains and Funding for supported chains.

Token Identifiers

Token identifier format varies by chain:

Solana: use the SPL mint pubkey (for example, EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v for USDC)
EVM: use the ERC-20 contract address (for example, 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 for USDC on Ethereum)
Native tokens: use "native" for SOL, ETH, MATIC, etc.

Use inspect_token to look up token details, or get_balance / get_portfolio to see what you hold.

Slippage

Slippage tolerance controls how much price movement you'll tolerate during a swap:

Default slippage tolerance is set in your policy (max_slippage_bps)
You can override per-swap with the slippage_bps parameter (basis points: 100 bps = 1%)
If actual slippage exceeds the limit, the swap is rejected before signing
For volatile tokens or low-liquidity pairs, you may need higher slippage

See Policy and Approvals for default slippage configuration.

Amount Formats

The amount and amount_units parameters control how amounts are interpreted:

amount is a decimal string (for example, "10", "0.5")
amount_units: "ui" (default) for human-readable amounts, "base" for raw units (lamports, wei)

Use "ui" unless you have a specific reason to use base units.

Typical Workflow

Check your balance: get_balance or get_portfolio
(Optional) Look up a token: inspect_token
Swap: swap_tokens with chain, token_in, token_out, amount_in
Confirm policy approval if prompted (via MCP elicitation)
Verify the swap landed: get_balance or get_portfolio

Example swap (Solana, SOL → USDC):

{
  "chain": "solana",
  "token_in": "native",
  "token_out": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
  "amount_in": "1",
  "amount_units": "ui"
}

Notes

Routing is automatic — Seashail picks the best route via Jupiter (Solana) or Uniswap (EVM)
For exact parameter details: swap_tokens reference
Related: Bridging Guide for cross-chain transfers before swapping