fix(did:aip): emit multicodec Ed25519 publicKeyMultibase (z6Mk form)

verificationMethod.publicKeyMultibase now encodes the 0xed01 ed25519-pub
multicodec prefix before base58btc, per the Ed25519VerificationKey2020 suite,
instead of a bare base58 of the raw key. Updates the resolver, method spec 4.2
plus example, and the devnet test assertion; bumps the resolver to 0.1.2. Also
tidies the register-test-agent doc comment (resolver, not resolver-test).

Author: dr-wilson-empty

packages/did-aip-driver/scripts/register-test-agent.ts

@@ -18,7 +18,7 @@
  *   npx tsx scripts/register-test-agent.ts
  *
  * On success it prints the canonical DID:
- *   did:aip:<owner_pubkey>:resolver-test
+ *   did:aip:<owner_pubkey>:resolver
  * Put that exact string into the driver's testIdentifiers (PR application.yml).
  */
 

packages/did-resolver/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@aipagents/did-resolver",
-  "version": "0.1.1",
+  "version": "0.1.2",
   "description": "Reference resolver for the did:aip W3C DID method (Solana-anchored agent identity)",
   "license": "MIT",
   "type": "module",

packages/did-resolver/src/resolver.ts

@@ -133,12 +133,27 @@ function failure(_did: string, error: "invalidDid" | "notFound" | "internalError
   };
 }
 
+/**
+ * Encode an Ed25519 public key as an Ed25519VerificationKey2020
+ * `publicKeyMultibase`: multibase-base58btc of the multicodec-prefixed key
+ * (0xed01 varint || 32-byte key). This yields the canonical `z6Mk...` form
+ * required by the suite, not a bare base58 of the raw key.
+ */
+function ed25519Multibase(base58Pubkey: string): string {
+  const raw = bs58.decode(base58Pubkey);
+  const prefixed = new Uint8Array(2 + raw.length);
+  prefixed[0] = 0xed; // ed25519-pub multicodec (varint low byte)
+  prefixed[1] = 0x01; // varint high byte
+  prefixed.set(raw, 2);
+  return `z${bs58.encode(prefixed)}`;
+}
+
 function buildDidDocument(did: string, record: AgentRecord): DidDocument {
   const verificationMethod: VerificationMethod = {
     id: `${did}#key-1`,
     type: "Ed25519VerificationKey2020",
     controller: did,
-    publicKeyMultibase: `z${record.walletAddress}`,
+    publicKeyMultibase: ed25519Multibase(record.walletAddress),
   };
 
   const service: ServiceEndpoint = {

packages/did-resolver/test/resolver.devnet.test.ts

@@ -134,7 +134,8 @@ test("resolver round-trip against live Devnet", { skip: loadOwner() === null },
   assert.ok(result.didDocument, "DID Document must be present");
   assert.equal(result.didDocument!.id, did);
   assert.equal(result.didDocument!.controller, did);
-  assert.equal(result.didDocument!.verificationMethod[0].publicKeyMultibase, `z${owner.publicKey.toBase58()}`);
+  const expectedMultibase = `z${bs58.encode(Uint8Array.from([0xed, 0x01, ...owner.publicKey.toBytes()]))}`;
+  assert.equal(result.didDocument!.verificationMethod[0].publicKeyMultibase, expectedMultibase, "publicKeyMultibase must be multicodec ed25519 (z6Mk form)");
   assert.equal(result.didDocument!.service[0].serviceEndpoint, "https://resolver.test/agent");
   assert.ok(result.agentRecord, "agentRecord must be returned");
   assert.equal(result.agentRecord!.agentId, agentId);

standards/did-aip-method-spec.md

@@ -119,10 +119,12 @@ The single canonical verification method **MUST** be constructed as:
   "id": "<DID>#key-1",
   "type": "Ed25519VerificationKey2020",
   "controller": "<DID>",
-  "publicKeyMultibase": "z<multibase-base58btc(record.wallet_address)>"
+  "publicKeyMultibase": "z<base58btc(0xed01 || record.wallet_address)>"
 }
 ```
 
+The `publicKeyMultibase` value **MUST** be the multibase-base58btc encoding (`z` prefix) of the multicodec-tagged key: the `ed25519-pub` prefix `0xed01` followed by the 32-byte Ed25519 public key. This is the canonical `z6Mk...` form required by the Ed25519VerificationKey2020 suite, not a bare base58 of the raw key.
+
 The `wallet_address` field of `AgentRecord` **MAY** differ from the `owner` field. This permits an operator (`owner`) to delegate signing authority for off-chain protocol messages to a separate hot key (`wallet_address`) without surrendering on-chain administrative control over the record. Resolvers **MUST** surface this distinction by exposing `controller` (derived from `owner`) and `verificationMethod.publicKeyMultibase` (derived from `wallet_address`) as independent values.
 
 ### 4.3 `authentication` and `assertionMethod`
@@ -169,7 +171,7 @@ The endpoint **MUST** be an `https://` URL or a fully-qualified protocol-prefixe
     "id": "did:aip:7xKXtg2CW87d97TXJSDpbD5jBkheTqA83TZRuJosgAsU:ada-research-001#key-1",
     "type": "Ed25519VerificationKey2020",
     "controller": "did:aip:7xKXtg2CW87d97TXJSDpbD5jBkheTqA83TZRuJosgAsU:ada-research-001",
-    "publicKeyMultibase": "z9WzDXwBbmkg8ZTbNMqUxvQRAyrZzDsGYdLVL9zYtAWWM"
+    "publicKeyMultibase": "z6MkmQaaUvGdqfc6FcJDz1BfSJdj1KyVsiQUjUUMjamtbPer"
   }],
   "authentication": ["did:aip:...:ada-research-001#key-1"],
   "assertionMethod":  ["did:aip:...:ada-research-001#key-1"],