diff --git a/node/spore_node/api/main.py b/node/spore_node/api/main.py
index 22fcb27..78a62b1 100644
--- a/node/spore_node/api/main.py
+++ b/node/spore_node/api/main.py
@@ -10,7 +10,7 @@ from fastapi import FastAPI
 
 from spore_node.config import SporeConfig
 from spore_node.db.connection import init_pool, close_pool
-from spore_node.api.routers import health, holons, governance
+from spore_node.api.routers import health, holons, governance, claims, intents, commitments
 
 log = logging.getLogger(__name__)
 
@@ -20,6 +20,9 @@ def mount_routers(app: FastAPI) -> None:
     app.include_router(health.router)
     app.include_router(holons.router)
     app.include_router(governance.router)
+    app.include_router(claims.router)
+    app.include_router(intents.router)
+    app.include_router(commitments.router)
 
 
 def create_standalone_app(cfg: SporeConfig | None = None) -> FastAPI:
diff --git a/node/spore_node/api/routers/claims.py b/node/spore_node/api/routers/claims.py
new file mode 100644
index 0000000..39afbf3
--- /dev/null
+++ b/node/spore_node/api/routers/claims.py
@@ -0,0 +1,314 @@
+"""Claims, Evidence, and Attestations endpoints."""
+
+import json
+import uuid
+from fastapi import APIRouter, HTTPException, Query
+from pydantic import BaseModel
+
+from spore_node.db.connection import get_pool
+from spore_node.rid_types import SporeClaim, SporeEvidence, SporeAttestation
+
+router = APIRouter(prefix="/claims", tags=["claims"])
+
+# --- Models ---
+
+VALID_STATUSES = ("proposed", "supported", "challenged", "superseded")
+VALID_TRANSITIONS = {
+    "proposed": ("supported", "challenged", "superseded"),
+    "supported": ("challenged", "superseded"),
+    "challenged": ("supported", "superseded"),
+    "superseded": (),
+}
+
+
+class ClaimCreate(BaseModel):
+    content: str
+    proposer_rid: str
+    confidence: float = 0.5
+    anchor_type: str = "assertion"
+    metadata: dict = {}
+
+
+class ClaimResponse(BaseModel):
+    id: str
+    rid: str
+    proposer_rid: str
+    content: str
+    status: str
+    confidence: float
+    anchor_type: str
+    metadata: dict
+
+
+class EvidenceCreate(BaseModel):
+    relation: str  # supports | challenges
+    body: str
+    provenance: dict = {}
+
+
+class EvidenceResponse(BaseModel):
+    id: str
+    rid: str
+    claim_id: str
+    relation: str
+    body: str
+    provenance: dict
+
+
+class AttestationCreate(BaseModel):
+    attester_rid: str
+    verdict: str  # endorse | dispute | abstain
+    strength: float = 1.0
+    reasoning: str = ""
+
+
+class AttestationResponse(BaseModel):
+    id: str
+    rid: str
+    claim_id: str
+    attester_rid: str
+    verdict: str
+    strength: float
+    reasoning: str
+
+
+class ClaimStrengthResponse(BaseModel):
+    claim_id: str
+    claim_rid: str
+    status: str
+    confidence: float
+    endorse_count: int
+    dispute_count: int
+    abstain_count: int
+    supporting_evidence: int
+    challenging_evidence: int
+    net_sentiment: float
+
+
+# --- Claims ---
+
+@router.post("", response_model=ClaimResponse, status_code=201)
+async def create_claim(data: ClaimCreate):
+    pool = get_pool()
+    claim_id = str(uuid.uuid4())
+    rid = str(SporeClaim(claim_id))
+
+    row = await pool.fetchrow(
+        """
+        INSERT INTO claims (id, rid, proposer_rid, content, confidence, anchor_type, metadata)
+        VALUES ($1, $2, $3, $4, $5, $6, $7::jsonb)
+        RETURNING id, rid, proposer_rid, content, status, confidence, anchor_type, metadata
+        """,
+        uuid.UUID(claim_id), rid, data.proposer_rid, data.content,
+        data.confidence, data.anchor_type, json.dumps(data.metadata),
+    )
+
+    await _log_event(pool, rid, "claim.created", {"content": data.content[:200]})
+    return _row_dict(row)
+
+
+@router.get("", response_model=list[ClaimResponse])
+async def list_claims(
+    status: str | None = None,
+    proposer_rid: str | None = None,
+    limit: int = Query(default=50, le=200),
+    offset: int = 0,
+):
+    pool = get_pool()
+    conditions, params = [], []
+    idx = 1
+
+    if status:
+        conditions.append(f"status = ${idx}")
+        params.append(status)
+        idx += 1
+    if proposer_rid:
+        conditions.append(f"proposer_rid = ${idx}")
+        params.append(proposer_rid)
+        idx += 1
+
+    where = "WHERE " + " AND ".join(conditions) if conditions else ""
+    rows = await pool.fetch(
+        f"SELECT * FROM claims {where} ORDER BY created_at DESC LIMIT ${idx} OFFSET ${idx+1}",
+        *params, limit, offset,
+    )
+    return [_row_dict(r) for r in rows]
+
+
+@router.get("/{claim_id}", response_model=ClaimResponse)
+async def get_claim(claim_id: str):
+    pool = get_pool()
+    row = await pool.fetchrow("SELECT * FROM claims WHERE id = $1", uuid.UUID(claim_id))
+    if not row:
+        raise HTTPException(404, "Claim not found")
+    return _row_dict(row)
+
+
+@router.patch("/{claim_id}/status")
+async def transition_claim_status(claim_id: str, new_status: str):
+    pool = get_pool()
+    row = await pool.fetchrow("SELECT status, rid FROM claims WHERE id = $1", uuid.UUID(claim_id))
+    if not row:
+        raise HTTPException(404, "Claim not found")
+
+    current = row["status"]
+    if new_status not in VALID_TRANSITIONS.get(current, ()):
+        raise HTTPException(
+            422,
+            f"Cannot transition from '{current}' to '{new_status}'. "
+            f"Valid: {VALID_TRANSITIONS.get(current, ())}",
+        )
+
+    await pool.execute(
+        "UPDATE claims SET status = $1, updated_at = now() WHERE id = $2",
+        new_status, uuid.UUID(claim_id),
+    )
+    await _log_event(pool, row["rid"], "claim.status_changed",
+                     {"from": current, "to": new_status})
+    return {"status": new_status, "previous": current}
+
+
+@router.get("/{claim_id}/strength", response_model=ClaimStrengthResponse)
+async def get_claim_strength(claim_id: str):
+    pool = get_pool()
+    # Refresh materialized view
+    await pool.execute("REFRESH MATERIALIZED VIEW CONCURRENTLY claim_strength")
+    row = await pool.fetchrow(
+        "SELECT * FROM claim_strength WHERE claim_id = $1", uuid.UUID(claim_id)
+    )
+    if not row:
+        raise HTTPException(404, "Claim not found")
+    d = dict(row)
+    d["claim_id"] = str(d["claim_id"])
+    return d
+
+
+# --- Evidence ---
+
+@router.post("/{claim_id}/evidence", response_model=EvidenceResponse, status_code=201)
+async def add_evidence(claim_id: str, data: EvidenceCreate):
+    if data.relation not in ("supports", "challenges"):
+        raise HTTPException(422, "relation must be 'supports' or 'challenges'")
+
+    pool = get_pool()
+    # Verify claim exists
+    claim = await pool.fetchrow("SELECT rid FROM claims WHERE id = $1", uuid.UUID(claim_id))
+    if not claim:
+        raise HTTPException(404, "Claim not found")
+
+    eid = str(uuid.uuid4())
+    rid = str(SporeEvidence(eid))
+
+    row = await pool.fetchrow(
+        """
+        INSERT INTO evidence (id, rid, claim_id, relation, body, provenance)
+        VALUES ($1, $2, $3, $4, $5, $6::jsonb)
+        RETURNING id, rid, claim_id, relation, body, provenance
+        """,
+        uuid.UUID(eid), rid, uuid.UUID(claim_id), data.relation,
+        data.body, json.dumps(data.provenance),
+    )
+
+    await _log_event(pool, claim["rid"], f"evidence.{data.relation}",
+                     {"evidence_rid": rid})
+    return _evidence_dict(row)
+
+
+@router.get("/{claim_id}/evidence", response_model=list[EvidenceResponse])
+async def list_evidence(claim_id: str, relation: str | None = None):
+    pool = get_pool()
+    if relation:
+        rows = await pool.fetch(
+            "SELECT * FROM evidence WHERE claim_id = $1 AND relation = $2 ORDER BY created_at",
+            uuid.UUID(claim_id), relation,
+        )
+    else:
+        rows = await pool.fetch(
+            "SELECT * FROM evidence WHERE claim_id = $1 ORDER BY created_at",
+            uuid.UUID(claim_id),
+        )
+    return [_evidence_dict(r) for r in rows]
+
+
+# --- Attestations ---
+
+@router.post("/{claim_id}/attestations", response_model=AttestationResponse, status_code=201)
+async def attest_claim(claim_id: str, data: AttestationCreate):
+    if data.verdict not in ("endorse", "dispute", "abstain"):
+        raise HTTPException(422, "verdict must be 'endorse', 'dispute', or 'abstain'")
+
+    pool = get_pool()
+    claim = await pool.fetchrow("SELECT rid FROM claims WHERE id = $1", uuid.UUID(claim_id))
+    if not claim:
+        raise HTTPException(404, "Claim not found")
+
+    aid = str(uuid.uuid4())
+    rid = str(SporeAttestation(aid))
+
+    try:
+        row = await pool.fetchrow(
+            """
+            INSERT INTO attestations (id, rid, claim_id, attester_rid, verdict, strength, reasoning)
+            VALUES ($1, $2, $3, $4, $5, $6, $7)
+            RETURNING id, rid, claim_id, attester_rid, verdict, strength, reasoning
+            """,
+            uuid.UUID(aid), rid, uuid.UUID(claim_id), data.attester_rid,
+            data.verdict, data.strength, data.reasoning,
+        )
+    except Exception as e:
+        if "unique" in str(e).lower():
+            raise HTTPException(409, f"Attester '{data.attester_rid}' already attested this claim")
+        raise
+
+    await _log_event(pool, claim["rid"], f"attestation.{data.verdict}",
+                     {"attester": data.attester_rid, "strength": data.strength})
+    return _attestation_dict(row)
+
+
+@router.get("/{claim_id}/attestations", response_model=list[AttestationResponse])
+async def list_attestations(claim_id: str, verdict: str | None = None):
+    pool = get_pool()
+    if verdict:
+        rows = await pool.fetch(
+            "SELECT * FROM attestations WHERE claim_id = $1 AND verdict = $2 ORDER BY created_at",
+            uuid.UUID(claim_id), verdict,
+        )
+    else:
+        rows = await pool.fetch(
+            "SELECT * FROM attestations WHERE claim_id = $1 ORDER BY created_at",
+            uuid.UUID(claim_id),
+        )
+    return [_attestation_dict(r) for r in rows]
+
+
+# --- Helpers ---
+
+def _row_dict(row) -> dict:
+    d = dict(row)
+    d["id"] = str(d["id"])
+    if isinstance(d.get("metadata"), str):
+        d["metadata"] = json.loads(d["metadata"])
+    return d
+
+
+def _evidence_dict(row) -> dict:
+    d = dict(row)
+    d["id"] = str(d["id"])
+    d["claim_id"] = str(d["claim_id"])
+    if isinstance(d.get("provenance"), str):
+        d["provenance"] = json.loads(d["provenance"])
+    return d
+
+
+def _attestation_dict(row) -> dict:
+    d = dict(row)
+    d["id"] = str(d["id"])
+    d["claim_id"] = str(d["claim_id"])
+    return d
+
+
+async def _log_event(pool, entity_rid: str, event_kind: str, payload: dict):
+    await pool.execute(
+        "INSERT INTO events (entity_rid, event_kind, payload) VALUES ($1, $2, $3::jsonb)",
+        entity_rid, event_kind, json.dumps(payload),
+    )
diff --git a/node/spore_node/api/routers/commitments.py b/node/spore_node/api/routers/commitments.py
new file mode 100644
index 0000000..44dec89
--- /dev/null
+++ b/node/spore_node/api/routers/commitments.py
@@ -0,0 +1,226 @@
+"""Commitment lifecycle endpoints with enforced state machine."""
+
+import json
+import uuid
+from fastapi import APIRouter, HTTPException, Query
+from pydantic import BaseModel
+
+from spore_node.db.connection import get_pool
+from spore_node.rid_types import SporeCommitment
+
+router = APIRouter(prefix="/commitments", tags=["commitments"])
+
+# State machine transitions
+VALID_TRANSITIONS = {
+    "proposed": ("verified", "cancelled"),
+    "verified": ("active", "cancelled"),
+    "active": ("evidence_linked", "disputed", "cancelled"),
+    "evidence_linked": ("redeemed", "disputed"),
+    "redeemed": (),
+    "disputed": ("resolved", "cancelled"),
+    "resolved": ("active", "redeemed"),
+    "cancelled": (),
+}
+
+
+class CommitmentCreate(BaseModel):
+    title: str
+    description: str = ""
+    proposer_rid: str
+    acceptor_rid: str | None = None
+    settlement_type: str = "attestation"
+    terms: dict = {}
+    metadata: dict = {}
+
+
+class CommitmentResponse(BaseModel):
+    id: str
+    rid: str
+    title: str
+    description: str
+    state: str
+    proposer_rid: str
+    acceptor_rid: str | None
+    settlement_type: str
+    terms: dict
+    metadata: dict
+
+
+class EvidenceLinkRequest(BaseModel):
+    evidence_id: str
+
+
+@router.post("", response_model=CommitmentResponse, status_code=201)
+async def create_commitment(data: CommitmentCreate):
+    pool = get_pool()
+    cid = str(uuid.uuid4())
+    rid = str(SporeCommitment(cid))
+
+    row = await pool.fetchrow(
+        """
+        INSERT INTO commitments (id, rid, title, description, proposer_rid, acceptor_rid,
+                                 settlement_type, terms, metadata)
+        VALUES ($1, $2, $3, $4, $5, $6, $7, $8::jsonb, $9::jsonb)
+        RETURNING *
+        """,
+        uuid.UUID(cid), rid, data.title, data.description, data.proposer_rid,
+        data.acceptor_rid, data.settlement_type,
+        json.dumps(data.terms), json.dumps(data.metadata),
+    )
+
+    await _log_event(pool, rid, "commitment.created",
+                     {"title": data.title, "proposer": data.proposer_rid})
+    return _row_dict(row)
+
+
+@router.get("", response_model=list[CommitmentResponse])
+async def list_commitments(
+    state: str | None = None,
+    proposer_rid: str | None = None,
+    acceptor_rid: str | None = None,
+    limit: int = Query(default=50, le=200),
+    offset: int = 0,
+):
+    pool = get_pool()
+    conditions, params = [], []
+    idx = 1
+
+    if state:
+        conditions.append(f"state = ${idx}")
+        params.append(state)
+        idx += 1
+    if proposer_rid:
+        conditions.append(f"proposer_rid = ${idx}")
+        params.append(proposer_rid)
+        idx += 1
+    if acceptor_rid:
+        conditions.append(f"acceptor_rid = ${idx}")
+        params.append(acceptor_rid)
+        idx += 1
+
+    where = "WHERE " + " AND ".join(conditions) if conditions else ""
+    rows = await pool.fetch(
+        f"SELECT * FROM commitments {where} ORDER BY created_at DESC LIMIT ${idx} OFFSET ${idx+1}",
+        *params, limit, offset,
+    )
+    return [_row_dict(r) for r in rows]
+
+
+@router.get("/{commitment_id}", response_model=CommitmentResponse)
+async def get_commitment(commitment_id: str):
+    pool = get_pool()
+    row = await pool.fetchrow(
+        "SELECT * FROM commitments WHERE id = $1", uuid.UUID(commitment_id)
+    )
+    if not row:
+        raise HTTPException(404, "Commitment not found")
+    return _row_dict(row)
+
+
+@router.patch("/{commitment_id}/state")
+async def transition_state(commitment_id: str, new_state: str):
+    pool = get_pool()
+    row = await pool.fetchrow(
+        "SELECT state, rid FROM commitments WHERE id = $1", uuid.UUID(commitment_id)
+    )
+    if not row:
+        raise HTTPException(404, "Commitment not found")
+
+    current = row["state"]
+    valid = VALID_TRANSITIONS.get(current, ())
+    if new_state not in valid:
+        raise HTTPException(
+            422,
+            f"Cannot transition from '{current}' to '{new_state}'. Valid: {valid}",
+        )
+
+    await pool.execute(
+        "UPDATE commitments SET state = $1, updated_at = now() WHERE id = $2",
+        new_state, uuid.UUID(commitment_id),
+    )
+    await _log_event(pool, row["rid"], "commitment.state_changed",
+                     {"from": current, "to": new_state})
+    return {"state": new_state, "previous": current}
+
+
+@router.post("/{commitment_id}/evidence", status_code=201)
+async def link_evidence(commitment_id: str, data: EvidenceLinkRequest):
+    pool = get_pool()
+
+    # Verify commitment exists and is in valid state
+    commitment = await pool.fetchrow(
+        "SELECT state, rid FROM commitments WHERE id = $1", uuid.UUID(commitment_id)
+    )
+    if not commitment:
+        raise HTTPException(404, "Commitment not found")
+    if commitment["state"] not in ("active", "evidence_linked"):
+        raise HTTPException(422, f"Cannot link evidence in state '{commitment['state']}'")
+
+    # Verify evidence exists
+    evidence = await pool.fetchrow(
+        "SELECT id FROM evidence WHERE id = $1", uuid.UUID(data.evidence_id)
+    )
+    if not evidence:
+        raise HTTPException(404, "Evidence not found")
+
+    try:
+        await pool.execute(
+            "INSERT INTO commitment_evidence (commitment_id, evidence_id) VALUES ($1, $2)",
+            uuid.UUID(commitment_id), uuid.UUID(data.evidence_id),
+        )
+    except Exception as e:
+        if "unique" in str(e).lower() or "duplicate" in str(e).lower():
+            raise HTTPException(409, "Evidence already linked")
+        raise
+
+    # Auto-transition to evidence_linked if currently active
+    if commitment["state"] == "active":
+        await pool.execute(
+            "UPDATE commitments SET state = 'evidence_linked', updated_at = now() WHERE id = $1",
+            uuid.UUID(commitment_id),
+        )
+
+    await _log_event(pool, commitment["rid"], "commitment.evidence_linked",
+                     {"evidence_id": data.evidence_id})
+    return {"linked": True, "commitment_id": commitment_id, "evidence_id": data.evidence_id}
+
+
+@router.get("/{commitment_id}/evidence")
+async def list_commitment_evidence(commitment_id: str):
+    pool = get_pool()
+    rows = await pool.fetch(
+        """
+        SELECT e.id, e.rid, e.relation, e.body, e.provenance, ce.linked_at
+        FROM commitment_evidence ce
+        JOIN evidence e ON e.id = ce.evidence_id
+        WHERE ce.commitment_id = $1
+        ORDER BY ce.linked_at
+        """,
+        uuid.UUID(commitment_id),
+    )
+    result = []
+    for r in rows:
+        d = dict(r)
+        d["id"] = str(d["id"])
+        if isinstance(d.get("provenance"), str):
+            d["provenance"] = json.loads(d["provenance"])
+        result.append(d)
+    return result
+
+
+# --- Helpers ---
+
+def _row_dict(row) -> dict:
+    d = dict(row)
+    d["id"] = str(d["id"])
+    for k in ("terms", "metadata"):
+        if isinstance(d.get(k), str):
+            d[k] = json.loads(d[k])
+    return d
+
+
+async def _log_event(pool, entity_rid: str, event_kind: str, payload: dict):
+    await pool.execute(
+        "INSERT INTO events (entity_rid, event_kind, payload) VALUES ($1, $2, $3::jsonb)",
+        entity_rid, event_kind, json.dumps(payload),
+    )
diff --git a/node/spore_node/api/routers/intents.py b/node/spore_node/api/routers/intents.py
new file mode 100644
index 0000000..bb6e1dc
--- /dev/null
+++ b/node/spore_node/api/routers/intents.py
@@ -0,0 +1,261 @@
+"""Intent publishing, matching, and lifecycle endpoints."""
+
+import json
+import uuid
+from fastapi import APIRouter, HTTPException, Query
+from pydantic import BaseModel
+
+from spore_node.db.connection import get_pool
+from spore_node.rid_types import SporeIntent
+
+router = APIRouter(prefix="/intents", tags=["intents"])
+
+VALID_STATES = ("open", "matched", "committed", "expired", "withdrawn")
+VALID_TRANSITIONS = {
+    "open": ("matched", "expired", "withdrawn"),
+    "matched": ("committed", "open", "withdrawn"),
+    "committed": ("expired",),
+    "expired": (),
+    "withdrawn": (),
+}
+COMPLEMENTARY_TYPES = {
+    "need": "offer",
+    "offer": "need",
+    "possibility": "possibility",
+}
+
+
+class IntentCreate(BaseModel):
+    publisher_rid: str
+    title: str
+    description: str = ""
+    intent_type: str  # need | offer | possibility
+    capacity: dict = {}
+    timing: dict = {}
+    governance_fit: list[str] = []
+    metadata: dict = {}
+
+
+class IntentResponse(BaseModel):
+    id: str
+    rid: str
+    publisher_rid: str
+    title: str
+    description: str
+    intent_type: str
+    capacity: dict
+    timing: dict
+    governance_fit: list[str]
+    state: str
+    metadata: dict
+
+
+class MatchResponse(BaseModel):
+    intent_a_id: str
+    intent_b_id: str
+    similarity: float
+    match_details: dict
+
+
+@router.post("", response_model=IntentResponse, status_code=201)
+async def publish_intent(data: IntentCreate):
+    if data.intent_type not in ("need", "offer", "possibility"):
+        raise HTTPException(422, "intent_type must be 'need', 'offer', or 'possibility'")
+
+    pool = get_pool()
+    iid = str(uuid.uuid4())
+    rid = str(SporeIntent(iid))
+
+    row = await pool.fetchrow(
+        """
+        INSERT INTO intents (id, rid, publisher_rid, title, description, intent_type,
+                            capacity, timing, governance_fit, metadata)
+        VALUES ($1, $2, $3, $4, $5, $6, $7::jsonb, $8::jsonb, $9, $10::jsonb)
+        RETURNING *
+        """,
+        uuid.UUID(iid), rid, data.publisher_rid, data.title, data.description,
+        data.intent_type, json.dumps(data.capacity), json.dumps(data.timing),
+        data.governance_fit, json.dumps(data.metadata),
+    )
+
+    await _log_event(pool, rid, "intent.published",
+                     {"type": data.intent_type, "title": data.title})
+
+    # Trigger matching (inline for now, ARQ worker in production)
+    await _compute_matches(pool, uuid.UUID(iid), data.intent_type)
+
+    return _row_dict(row)
+
+
+@router.get("", response_model=list[IntentResponse])
+async def list_intents(
+    intent_type: str | None = None,
+    state: str | None = None,
+    publisher_rid: str | None = None,
+    limit: int = Query(default=50, le=200),
+    offset: int = 0,
+):
+    pool = get_pool()
+    conditions, params = [], []
+    idx = 1
+
+    if intent_type:
+        conditions.append(f"intent_type = ${idx}")
+        params.append(intent_type)
+        idx += 1
+    if state:
+        conditions.append(f"state = ${idx}")
+        params.append(state)
+        idx += 1
+    if publisher_rid:
+        conditions.append(f"publisher_rid = ${idx}")
+        params.append(publisher_rid)
+        idx += 1
+
+    where = "WHERE " + " AND ".join(conditions) if conditions else ""
+    rows = await pool.fetch(
+        f"SELECT * FROM intents {where} ORDER BY created_at DESC LIMIT ${idx} OFFSET ${idx+1}",
+        *params, limit, offset,
+    )
+    return [_row_dict(r) for r in rows]
+
+
+@router.get("/{intent_id}", response_model=IntentResponse)
+async def get_intent(intent_id: str):
+    pool = get_pool()
+    row = await pool.fetchrow("SELECT * FROM intents WHERE id = $1", uuid.UUID(intent_id))
+    if not row:
+        raise HTTPException(404, "Intent not found")
+    return _row_dict(row)
+
+
+@router.patch("/{intent_id}/state")
+async def transition_intent_state(intent_id: str, new_state: str):
+    pool = get_pool()
+    row = await pool.fetchrow("SELECT state, rid FROM intents WHERE id = $1", uuid.UUID(intent_id))
+    if not row:
+        raise HTTPException(404, "Intent not found")
+
+    current = row["state"]
+    if new_state not in VALID_TRANSITIONS.get(current, ()):
+        raise HTTPException(
+            422,
+            f"Cannot transition from '{current}' to '{new_state}'. "
+            f"Valid: {VALID_TRANSITIONS.get(current, ())}",
+        )
+
+    await pool.execute(
+        "UPDATE intents SET state = $1, updated_at = now() WHERE id = $2",
+        new_state, uuid.UUID(intent_id),
+    )
+    await _log_event(pool, row["rid"], "intent.state_changed",
+                     {"from": current, "to": new_state})
+    return {"state": new_state, "previous": current}
+
+
+@router.get("/{intent_id}/matches", response_model=list[MatchResponse])
+async def get_matches(intent_id: str, min_similarity: float = 0.0):
+    pool = get_pool()
+    uid = uuid.UUID(intent_id)
+    rows = await pool.fetch(
+        """
+        SELECT * FROM intent_matches
+        WHERE (intent_a_id = $1 OR intent_b_id = $1) AND similarity >= $2
+        ORDER BY similarity DESC
+        """,
+        uid, min_similarity,
+    )
+    return [_match_dict(r) for r in rows]
+
+
+# --- Matching logic ---
+
+async def _compute_matches(pool, intent_id: uuid.UUID, intent_type: str):
+    """Compute matches between this intent and complementary open intents.
+
+    Scoring: governance_fit overlap (primary), with text similarity as tiebreaker.
+    Embedding-based similarity added when embeddings are available.
+    """
+    complement = COMPLEMENTARY_TYPES.get(intent_type, "")
+    if not complement:
+        return
+
+    intent = await pool.fetchrow("SELECT * FROM intents WHERE id = $1", intent_id)
+    if not intent:
+        return
+
+    # Find complementary open intents
+    candidates = await pool.fetch(
+        """
+        SELECT * FROM intents
+        WHERE intent_type = $1 AND state = 'open' AND id != $2
+        """,
+        complement, intent_id,
+    )
+
+    my_gov = set(intent["governance_fit"] or [])
+
+    for cand in candidates:
+        cand_gov = set(cand["governance_fit"] or [])
+
+        # Governance fit overlap
+        if my_gov and cand_gov:
+            gov_score = len(my_gov & cand_gov) / len(my_gov | cand_gov)
+        elif not my_gov and not cand_gov:
+            gov_score = 0.5  # neutral
+        else:
+            gov_score = 0.1
+
+        # Simple text overlap as proxy until embeddings available
+        my_words = set(intent["title"].lower().split() + intent["description"].lower().split())
+        cand_words = set(cand["title"].lower().split() + cand["description"].lower().split())
+        text_score = len(my_words & cand_words) / max(len(my_words | cand_words), 1)
+
+        similarity = 0.6 * gov_score + 0.4 * text_score
+
+        if similarity < 0.05:
+            continue
+
+        # Ensure consistent ordering for unique constraint
+        a_id, b_id = sorted([intent_id, cand["id"]], key=str)
+
+        await pool.execute(
+            """
+            INSERT INTO intent_matches (intent_a_id, intent_b_id, similarity, match_details)
+            VALUES ($1, $2, $3, $4::jsonb)
+            ON CONFLICT (intent_a_id, intent_b_id)
+            DO UPDATE SET similarity = $3, match_details = $4::jsonb
+            """,
+            a_id, b_id, round(similarity, 4),
+            json.dumps({"gov_score": round(gov_score, 4), "text_score": round(text_score, 4)}),
+        )
+
+
+# --- Helpers ---
+
+def _row_dict(row) -> dict:
+    d = dict(row)
+    d["id"] = str(d["id"])
+    for k in ("capacity", "timing", "metadata"):
+        if isinstance(d.get(k), str):
+            d[k] = json.loads(d[k])
+    if d.get("governance_fit") is None:
+        d["governance_fit"] = []
+    return d
+
+
+def _match_dict(row) -> dict:
+    d = dict(row)
+    d.pop("id", None)
+    d["intent_a_id"] = str(d["intent_a_id"])
+    d["intent_b_id"] = str(d["intent_b_id"])
+    if isinstance(d.get("match_details"), str):
+        d["match_details"] = json.loads(d["match_details"])
+    return d
+
+
+async def _log_event(pool, entity_rid: str, event_kind: str, payload: dict):
+    await pool.execute(
+        "INSERT INTO events (entity_rid, event_kind, payload) VALUES ($1, $2, $3::jsonb)",
+        entity_rid, event_kind, json.dumps(payload),
+    )
diff --git a/node/spore_node/db/migrations/002_primitives.sql b/node/spore_node/db/migrations/002_primitives.sql
new file mode 100644
index 0000000..50c8348
--- /dev/null
+++ b/node/spore_node/db/migrations/002_primitives.sql
@@ -0,0 +1,166 @@
+-- Spore Agent Commons — Core Primitives
+-- Claims, Evidence, Attestations, Intents, Commitments
+
+-- ============================================================
+-- Claims (knowledge claims in the commons)
+-- ============================================================
+CREATE TABLE IF NOT EXISTS claims (
+    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
+    rid TEXT UNIQUE NOT NULL,
+    proposer_rid TEXT NOT NULL,
+    content TEXT NOT NULL,
+    status TEXT NOT NULL DEFAULT 'proposed'
+        CHECK (status IN ('proposed', 'supported', 'challenged', 'superseded')),
+    confidence FLOAT DEFAULT 0.5,
+    anchor_type TEXT DEFAULT 'assertion',
+    embedding vector(1024),
+    metadata JSONB NOT NULL DEFAULT '{}',
+    created_at TIMESTAMPTZ NOT NULL DEFAULT now(),
+    updated_at TIMESTAMPTZ NOT NULL DEFAULT now()
+);
+
+CREATE INDEX IF NOT EXISTS idx_claims_proposer ON claims (proposer_rid);
+CREATE INDEX IF NOT EXISTS idx_claims_status ON claims (status);
+CREATE INDEX IF NOT EXISTS idx_claims_metadata ON claims USING GIN (metadata);
+
+-- ============================================================
+-- Evidence (supports or challenges a claim)
+-- ============================================================
+CREATE TABLE IF NOT EXISTS evidence (
+    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
+    rid TEXT UNIQUE NOT NULL,
+    claim_id UUID NOT NULL REFERENCES claims(id) ON DELETE CASCADE,
+    relation TEXT NOT NULL CHECK (relation IN ('supports', 'challenges')),
+    body TEXT NOT NULL,
+    provenance JSONB NOT NULL DEFAULT '{}',
+    embedding vector(1024),
+    created_at TIMESTAMPTZ NOT NULL DEFAULT now()
+);
+
+CREATE INDEX IF NOT EXISTS idx_evidence_claim ON evidence (claim_id);
+CREATE INDEX IF NOT EXISTS idx_evidence_relation ON evidence (relation);
+
+-- ============================================================
+-- Attestations (endorse/dispute/abstain on a claim)
+-- ============================================================
+CREATE TABLE IF NOT EXISTS attestations (
+    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
+    rid TEXT UNIQUE NOT NULL,
+    claim_id UUID NOT NULL REFERENCES claims(id) ON DELETE CASCADE,
+    attester_rid TEXT NOT NULL,
+    verdict TEXT NOT NULL CHECK (verdict IN ('endorse', 'dispute', 'abstain')),
+    strength FLOAT NOT NULL DEFAULT 1.0,
+    reasoning TEXT DEFAULT '',
+    created_at TIMESTAMPTZ NOT NULL DEFAULT now(),
+    UNIQUE (claim_id, attester_rid)
+);
+
+CREATE INDEX IF NOT EXISTS idx_attestations_claim ON attestations (claim_id);
+CREATE INDEX IF NOT EXISTS idx_attestations_attester ON attestations (attester_rid);
+
+-- ============================================================
+-- Claim strength (materialized view)
+-- ============================================================
+CREATE MATERIALIZED VIEW IF NOT EXISTS claim_strength AS
+SELECT
+    c.id AS claim_id,
+    c.rid AS claim_rid,
+    c.status,
+    c.confidence,
+    COUNT(DISTINCT CASE WHEN a.verdict = 'endorse' THEN a.id END) AS endorse_count,
+    COUNT(DISTINCT CASE WHEN a.verdict = 'dispute' THEN a.id END) AS dispute_count,
+    COUNT(DISTINCT CASE WHEN a.verdict = 'abstain' THEN a.id END) AS abstain_count,
+    COUNT(DISTINCT CASE WHEN e.relation = 'supports' THEN e.id END) AS supporting_evidence,
+    COUNT(DISTINCT CASE WHEN e.relation = 'challenges' THEN e.id END) AS challenging_evidence,
+    COALESCE(
+        (COUNT(DISTINCT CASE WHEN a.verdict = 'endorse' THEN a.id END)::float -
+         COUNT(DISTINCT CASE WHEN a.verdict = 'dispute' THEN a.id END)::float) /
+        NULLIF(COUNT(DISTINCT a.id)::float, 0),
+        0
+    ) AS net_sentiment,
+    MAX(GREATEST(
+        COALESCE(MAX(a.created_at), c.created_at),
+        COALESCE(MAX(e.created_at), c.created_at)
+    )) AS last_activity
+FROM claims c
+LEFT JOIN attestations a ON a.claim_id = c.id
+LEFT JOIN evidence e ON e.claim_id = c.id
+GROUP BY c.id, c.rid, c.status, c.confidence;
+
+CREATE UNIQUE INDEX IF NOT EXISTS idx_claim_strength_id ON claim_strength (claim_id);
+
+-- ============================================================
+-- Intents (need/offer/possibility)
+-- ============================================================
+CREATE TABLE IF NOT EXISTS intents (
+    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
+    rid TEXT UNIQUE NOT NULL,
+    publisher_rid TEXT NOT NULL,
+    title TEXT NOT NULL,
+    description TEXT NOT NULL DEFAULT '',
+    intent_type TEXT NOT NULL CHECK (intent_type IN ('need', 'offer', 'possibility')),
+    capacity JSONB NOT NULL DEFAULT '{}',
+    timing JSONB NOT NULL DEFAULT '{}',
+    governance_fit TEXT[] DEFAULT '{}',
+    state TEXT NOT NULL DEFAULT 'open'
+        CHECK (state IN ('open', 'matched', 'committed', 'expired', 'withdrawn')),
+    embedding vector(1024),
+    metadata JSONB NOT NULL DEFAULT '{}',
+    created_at TIMESTAMPTZ NOT NULL DEFAULT now(),
+    updated_at TIMESTAMPTZ NOT NULL DEFAULT now()
+);
+
+CREATE INDEX IF NOT EXISTS idx_intents_publisher ON intents (publisher_rid);
+CREATE INDEX IF NOT EXISTS idx_intents_type ON intents (intent_type);
+CREATE INDEX IF NOT EXISTS idx_intents_state ON intents (state);
+
+-- ============================================================
+-- Intent matches (computed similarity pairs)
+-- ============================================================
+CREATE TABLE IF NOT EXISTS intent_matches (
+    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
+    intent_a_id UUID NOT NULL REFERENCES intents(id) ON DELETE CASCADE,
+    intent_b_id UUID NOT NULL REFERENCES intents(id) ON DELETE CASCADE,
+    similarity FLOAT NOT NULL,
+    match_details JSONB NOT NULL DEFAULT '{}',
+    created_at TIMESTAMPTZ NOT NULL DEFAULT now(),
+    UNIQUE (intent_a_id, intent_b_id),
+    CHECK (intent_a_id < intent_b_id)
+);
+
+CREATE INDEX IF NOT EXISTS idx_intent_matches_a ON intent_matches (intent_a_id);
+CREATE INDEX IF NOT EXISTS idx_intent_matches_b ON intent_matches (intent_b_id);
+
+-- ============================================================
+-- Commitments (lifecycle state machine)
+-- ============================================================
+CREATE TABLE IF NOT EXISTS commitments (
+    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
+    rid TEXT UNIQUE NOT NULL,
+    title TEXT NOT NULL,
+    description TEXT NOT NULL DEFAULT '',
+    state TEXT NOT NULL DEFAULT 'proposed'
+        CHECK (state IN ('proposed', 'verified', 'active', 'evidence_linked',
+                         'redeemed', 'disputed', 'resolved', 'cancelled')),
+    proposer_rid TEXT NOT NULL,
+    acceptor_rid TEXT,
+    settlement_type TEXT DEFAULT 'attestation',
+    terms JSONB NOT NULL DEFAULT '{}',
+    metadata JSONB NOT NULL DEFAULT '{}',
+    created_at TIMESTAMPTZ NOT NULL DEFAULT now(),
+    updated_at TIMESTAMPTZ NOT NULL DEFAULT now()
+);
+
+CREATE INDEX IF NOT EXISTS idx_commitments_state ON commitments (state);
+CREATE INDEX IF NOT EXISTS idx_commitments_proposer ON commitments (proposer_rid);
+CREATE INDEX IF NOT EXISTS idx_commitments_acceptor ON commitments (acceptor_rid);
+
+-- ============================================================
+-- Commitment-Evidence links
+-- ============================================================
+CREATE TABLE IF NOT EXISTS commitment_evidence (
+    commitment_id UUID NOT NULL REFERENCES commitments(id) ON DELETE CASCADE,
+    evidence_id UUID NOT NULL REFERENCES evidence(id) ON DELETE CASCADE,
+    linked_at TIMESTAMPTZ NOT NULL DEFAULT now(),
+    PRIMARY KEY (commitment_id, evidence_id)
+);