Agent-safe signing · Agent framework

Coldstar vs Solana Agent Kit

Solana Agent Kit is the de-facto toolkit for connecting an LLM to Solana protocols: LangChain, Vercel AI, and OpenAI adapters, dozens of protocol plugins. It is not a signer. Its default wallet is a raw keypair in memory, and its BaseWallet interface exists precisely so you can replace that. Coldstar is a replacement.

Last reviewed 2026-09-04 · Facts link to first-party sources below · Corrections welcome

Pick Solana Agent Kit if

  • You need the protocol coverage: swaps, staking, NFTs, lending, and the rest, as agent tools.
  • You want framework adapters for LangChain, Vercel AI SDK, or OpenAI.
  • You are on devnet and the default KeypairWallet is fine for now.

Pick Coldstar if

  • You are asking a different question: what signs. Coldstar answers that; Solana Agent Kit does not try to.
  • You want the agent's key bounded by policy with a cold root.
  • You want a signer that is not a hosted vendor.

Use both when

This is the intended pairing. Solana Agent Kit builds the transactions; a Coldstar-backed BaseWallet decides whether they get signed.

Side by side

ColdstarSolana Agent Kit
Who holds the root keyYou. The cold root lives encrypted on your own USB drive. No vendor holds a key, a share, or an account.By default, the agent process: the README builds a KeypairWallet from Keypair.fromSecretKey(bs58.decode(SOLANA_PRIVATE_KEY)). The BaseWallet interface lets you substitute any signer.
Where the key livesOn your machine. The air-gapped root signs a bounded policy envelope; a disposable session key signs routine transactions inside it.In-process memory and an environment variable by default. Examples ship for Turnkey, Privy, Crossmint, Para, and Phantom embedded wallets.
Policy enginePer-transaction limit, daily cap, program allowlist, recipient allowlist and blocklist, escalate-above threshold. Evaluated locally, first match wins, before any signature exists.None in core. Any policy comes from whatever signer you plug in.
Out-of-policy transactionsESCALATE to a human over air-gapped QR, or REJECT. No signature is produced for a rejected transaction.Not applicable in core.
Cold / offline rootYes — the root key never touches a networked machine.No.
Agent integrationFramework-agnostic: the agent proposes an unsigned transaction, the signer decides. CLI signer today; MCP server in progress.It is the agent integration: tool adapters for the major frameworks and protocol plugins.
Solana supportSolana mainnet. Core is chain-agnostic; EVM signing exists.Yes; Solana only.
Source & self-hostingOpen source (MIT), self-hosted. No API key, no SaaS dependency, nothing to go down.Apache-2.0, fully open, self-hosted.
PricingFree software plus a ~$10 drive.Free.
MaturityBeta — the signing core and policy engine are in scope for the planned independent audit.Production toolkit with a large plugin ecosystem; v2 default branch.

There is no fight here. Solana Agent Kit is the best way to give an agent Solana capabilities; Coldstar is a way to make sure those capabilities have limits.

Where each one wins

Where Solana Agent Kit wins

  • Coverage. The broadest set of Solana protocol actions as agent tools.
  • Adapters. LangChain, Vercel AI SDK, OpenAI, and more.
  • Pluggable wallets. BaseWallet makes the signer a swap-in.

Where Coldstar wins

  • It is a signer. Policy, cold root, escalation; Solana Agent Kit has none of these by design.
  • Self-hosted signer. The other shipped examples are hosted vendors.
  • Bounded default. Replacing KeypairWallet with a Coldstar session key turns "lose everything" into "lose at most the policy".

What you are actually trusting

Solana Agent Kit's BaseWallet interface is five methods: public key, sign transaction, sign all, sign and send, sign message. The shipped KeypairWallet implements them with a raw Keypair and tweetnacl, which is the right default for a toolkit and the wrong default for money. The maintainers know this; the embedded-wallet examples exist to move the key out of the process.

A Coldstar-backed BaseWallet signs with a disposable session key inside a policy envelope the cold root authorised offline. Sign-transaction calls pass through the local rule list first; a REJECT returns no signature; an ESCALATE waits for a human over QR.

Solana Agent Kit is production tooling. Coldstar is beta, pre-audit; a Coldstar BaseWallet adapter is the integration to watch for.

Using Solana Agent Kit and Coldstar together

Implement BaseWallet with a Coldstar session key and keep every plugin and adapter you already use. Nothing above the wallet changes.

Frequently asked questions

Is Solana Agent Kit insecure?

No. It is a toolkit that, by default, signs with a keypair you give it. Security is the job of the signer you plug in; the kit makes that pluggable.

Which signers does Solana Agent Kit ship examples for?

Turnkey, Privy, Crossmint, Para, and Phantom embedded wallets, plus the default KeypairWallet. All of the vendor options are hosted; Coldstar would be the self-hosted, cold-rooted one.

Does Coldstar replace Solana Agent Kit?

No. Coldstar has no protocol plugins or framework adapters. It replaces the wallet underneath them.

Try Coldstar in two minutes

Open source, MIT. macOS, Linux, Windows — and on the Solana Seeker dApp Store.

pip install coldstar

Related comparisons

Sources

  1. Solana Agent Kit repository (README, KeypairWallet, BaseWallet, embedded-wallet examples)
  2. SendAI docs: introduction

Third-party facts were checked against the vendor's own pages on the date above. Pricing and feature sets change; if something here is out of date, tell us and we will fix it.