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@three-ws/agent-protocol-sdk
Advanced tools
Record verifiable agent-to-agent skill invocations on Solana, via the agent_invocation Anchor program.
Install · Quick start · API · Requirements · three.ws
Thin, typed client for the
agent_invocationSolana program. One agent calls a skill on another agent; the call is validated client-side, built as an Anchor instruction, and submitted on-chain, where it emits aSkillInvokedevent that anyone can verify. Built for three.ws agent-to-agent (A2A) coordination.
Live. The
agent_invocationprogram is deployed and the SDK targets it by default.AGENT_INVOCATION_PROGRAM_IDisAgEntJDMi1A7UadCoYcx6Fm3gusNk8SHLCi7vSUa4Zfo— the same program id on mainnet-beta and devnet. Just pointconnectionat the cluster you want; theprogramIdparam is optional and only needed to target a different deployment. Deploy addresses, signatures, and the upgrade authority are recorded incontracts/agent-invocation/DEPLOYMENT.md.
npm install @three-ws/agent-protocol-sdk @solana/web3.js @coral-xyz/anchor
@solana/web3.js (^1.98) and @coral-xyz/anchor (^0.32) are direct
dependencies and are installed alongside the package.
import { Connection, Keypair, PublicKey } from '@solana/web3.js';
import { invokeSkill } from '@three-ws/agent-protocol-sdk';
// mainnet-beta by default; use 'https://api.devnet.solana.com' for devnet.
const connection = new Connection('https://api.mainnet-beta.solana.com', 'confirmed');
const invokerAuthority = Keypair.fromSecretKey(/* your secret key bytes */);
const targetAuthority = new PublicKey('<authority that owns the target agent>');
const signature = await invokeSkill({
connection,
invokerAuthority, // signs + pays
targetAuthority, // target agent PDA is derived from this
skillName: 'summarize', // 1–64 bytes
parameters: JSON.stringify({ url: 'https://example.com' }), // ≤512 bytes
// programId is optional — defaults to the live AGENT_INVOCATION_PROGRAM_ID.
});
console.log('invocation tx:', signature);
invokeSkill validates the inputs, derives both the invoker and target agent
PDAs, builds the invoke_skill instruction, submits it, and returns the
confirmed transaction signature.
invokeSkill(params): Promise<string>Records a skill invocation from one agent to another and returns the confirmed transaction signature.
| Param | Type | Description |
|---|---|---|
connection | Connection | Live Solana connection used to build and send the tx. |
invokerAuthority | Keypair | Owns the invoking agent. Signs and pays. |
targetAuthority | PublicKey | Owns the target agent; its PDA is re-derived from this. |
skillName | string | Skill identifier, 1–64 bytes (UTF-8). |
parameters | string | Opaque parameter blob, ≤512 bytes (typically JSON). |
programId | PublicKey (optional) | Override the program id. Required on any live cluster. |
Throws if skillName is empty, skillName exceeds MAX_SKILL_NAME_LEN bytes,
or parameters exceeds MAX_PARAMETERS_LEN bytes — so you get a clear local
error instead of a failed on-chain simulation.
deriveAgentPda(authority, programId?): [PublicKey, number]Derives an agent's program-derived address from the authority that owns it.
Matches the program's seeds = [b"agent", authority]. Pass your deployed
programId to derive against a live cluster; otherwise it uses
AGENT_INVOCATION_PROGRAM_ID.
import { deriveAgentPda } from '@three-ws/agent-protocol-sdk';
const [agentPda, bump] = deriveAgentPda(authority, programId);
| Export | Type | Value / meaning |
|---|---|---|
MAX_SKILL_NAME_LEN | number | 64 — max skillName length in bytes. |
MAX_PARAMETERS_LEN | number | 512 — max parameters length in bytes. |
AGENT_INVOCATION_PROGRAM_ID | string | Live program id (AgEnt…Zfo), same on mainnet + devnet. |
IDL | Anchor Idl | The agent_invocation IDL (Anchor 0.30+ format). |
AgentInvocation | type | TypeScript type of IDL for new Program<AgentInvocation>(...). |
InvokeSkillParams | interface | Parameter shape for invokeSkill. |
The program exposes one instruction, invoke_skill(skill_name, parameters), over
four accounts (invoker_agent PDA, invoker_authority signer, target_authority,
target_agent PDA) plus the system program. A successful call emits a
SkillInvoked event with invoker_agent, target_agent, invoker_authority,
skill_name, parameters, and a timestamp. The program's error codes
(EmptySkillName, SkillNameTooLong, ParametersTooLong) mirror the client-side
validation above.
>= 18.@solana/web3.js@^1.98, @coral-xyz/anchor@^0.32.invokerAuthority signs and pays the transaction fee, so
it needs a small SOL balance on the target cluster. The program itself is
already deployed — AGENT_INVOCATION_PROGRAM_ID points at the live program on
mainnet and devnet.
Part of the three.ws SDK suite — 3D AI agents, on-chain identity, and agent payments.
Website · Changelog · GitHub
FAQs
SDK for the on-chain agent-to-agent invocation protocol.
The npm package @three-ws/agent-protocol-sdk receives a total of 5 weekly downloads. As such, @three-ws/agent-protocol-sdk popularity was classified as not popular.
We found that @three-ws/agent-protocol-sdk demonstrated a healthy version release cadence and project activity because the last version was released less than a year ago. It has 1 open source maintainer collaborating on the project.
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