diff --git a/cmd/orchestra-worker/phase_test.go b/cmd/orchestra-worker/phase_test.go
index d47fee3..a756e24 100644
--- a/cmd/orchestra-worker/phase_test.go
+++ b/cmd/orchestra-worker/phase_test.go
@@ -155,7 +155,7 @@ func TestPhaseRequestCarriesTheSealedArtifact(t *testing.T) {
 	w.tasks["task"] = task
 	w.sessions["task"] = herdr.Session{PaneID: "pane", Worktree: wt, Phase: string(domain.WorkPhaseResearch)}
 
-	sealed, err := workphase.Encode(workphase.Research{Findings: []workphase.Finding{{Claim: "c", Evidence: "e"}}})
+	sealed, err := workphase.Encode(workphase.Research{Findings: []workphase.Finding{{ID: "r1", Confidence: workphase.Fact, Claim: "c", Evidence: "e"}}})
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/internal/agentctx/agentctx.go b/internal/agentctx/agentctx.go
index 524899a..1b59c6c 100644
--- a/internal/agentctx/agentctx.go
+++ b/internal/agentctx/agentctx.go
@@ -430,7 +430,10 @@ func renderSealed(in Input) string {
 	if research != nil {
 		b.WriteString("\n## Accepted research\n\n")
 		for _, f := range research.Findings {
-			fmt.Fprintf(&b, "- %s (evidence: %s)\n", collapse(f.Claim), collapse(f.Evidence))
+			// The id is printed so a plan can cite "research:<id>" and a reader
+			// can resolve it. Plan seal validation checks every citation
+			// against this same artifact.
+			fmt.Fprintf(&b, "- [%s] %s: %s (evidence: %s)\n", f.ID, f.Confidence, collapse(f.Claim), collapse(f.Evidence))
 		}
 		for _, c := range research.Code {
 			fmt.Fprintf(&b, "- relevant: %s (%s)\n", collapse(c.Path), collapse(c.Why))
diff --git a/internal/integration/acefca_test.go b/internal/integration/acefca_test.go
index bb99fe1..da07e8c 100644
--- a/internal/integration/acefca_test.go
+++ b/internal/integration/acefca_test.go
@@ -230,7 +230,7 @@ func advance(t *testing.T, s *store.Store, project registry.Project, taskID stri
 func sealedResearch(t *testing.T) []byte {
 	t.Helper()
 	b, err := workphase.Encode(workphase.Research{
-		Findings: []workphase.Finding{{Claim: "attribution runs per figure", Evidence: "internal/attr/attr.go:88"}},
+		Findings: []workphase.Finding{{ID: "r1", Confidence: workphase.Fact, Claim: "attribution runs per figure", Evidence: "internal/attr/attr.go:88"}},
 		DeadEnds: []workphase.DeadEnd{{Tried: "figure plurality", WhyFailed: "no measured gain"}},
 	})
 	if err != nil {
diff --git a/internal/integration/phase_protocol_test.go b/internal/integration/phase_protocol_test.go
index bb88daf..df4c0c7 100644
--- a/internal/integration/phase_protocol_test.go
+++ b/internal/integration/phase_protocol_test.go
@@ -120,7 +120,7 @@ func TestPhaseRequestPathSealsAndFences(t *testing.T) {
 	}
 }
 
-var researchArtifact = workphase.Research{Findings: []workphase.Finding{{Claim: "runs per figure", Evidence: "attr.go:88"}}}
+var researchArtifact = workphase.Research{Findings: []workphase.Finding{{ID: "r1", Confidence: workphase.Fact, Claim: "runs per figure", Evidence: "attr.go:88"}}}
 
 func sealed(t *testing.T, v interface{ Validate() error }) []byte {
 	t.Helper()
diff --git a/internal/operations/trajectory.go b/internal/operations/trajectory.go
index 9c246ce..1ba3e7e 100644
--- a/internal/operations/trajectory.go
+++ b/internal/operations/trajectory.go
@@ -104,7 +104,7 @@ func TrajectoryGatePacket(s *store.Store, t domain.Task, from, to domain.WorkPha
 	}
 	if t.ResearchRef != "" {
 		if raw, err := s.Artifact(t.ResearchRef); err == nil {
-			if r, err := workphase.DecodeResearch(raw); err == nil {
+			if r, err := workphase.DecodeStoredResearch(raw); err == nil {
 				b.WriteString("\nWhat research established:\n")
 				for _, f := range r.Findings {
 					fmt.Fprintf(&b, "- %s (%s)\n", oneLine(f.Claim), oneLine(f.Evidence))
diff --git a/internal/operations/workphase_test.go b/internal/operations/workphase_test.go
index 9ee5c32..7700dc4 100644
--- a/internal/operations/workphase_test.go
+++ b/internal/operations/workphase_test.go
@@ -46,7 +46,7 @@ func sealed(t *testing.T, v interface{ Validate() error }) []byte {
 	return b
 }
 
-var research = workphase.Research{Findings: []workphase.Finding{{Claim: "runs per figure", Evidence: "attr.go:88"}}}
+var research = workphase.Research{Findings: []workphase.Finding{{ID: "r1", Confidence: workphase.Fact, Claim: "runs per figure", Evidence: "attr.go:88"}}}
 var plan = workphase.Plan{Changes: []workphase.Change{{Target: "attr.go", Intent: "aggregate per person"}}}
 
 func TestFullPhasePathSealsEachArtifact(t *testing.T) {
diff --git a/internal/orchestrator/orchestrator.go b/internal/orchestrator/orchestrator.go
index 16b5af7..69cffd0 100644
--- a/internal/orchestrator/orchestrator.go
+++ b/internal/orchestrator/orchestrator.go
@@ -1296,7 +1296,7 @@ func (c *Coordinator) research(ref string) (*workphase.Research, error) {
 	if err != nil {
 		return nil, err
 	}
-	r, err := workphase.DecodeResearch(b)
+	r, err := workphase.DecodeStoredResearch(b)
 	if err != nil {
 		return nil, err
 	}
diff --git a/internal/workphase/workphase.go b/internal/workphase/workphase.go
index 60f2c9c..de32414 100644
--- a/internal/workphase/workphase.go
+++ b/internal/workphase/workphase.go
@@ -11,16 +11,51 @@ package workphase
 import (
 	"encoding/json"
 	"fmt"
+	"regexp"
 	"sort"
 	"strings"
 )
 
-// Finding is one thing research established, with the evidence for it.
-type Finding struct {
-	Claim    string `json:"claim"`
-	Evidence string `json:"evidence"`
+// Confidence separates what research observed from what it concluded. A plan
+// that cites an assumption as if it were a fact is the failure this exists to
+// make visible.
+type Confidence string
+
+const (
+	// Fact is directly observed in the repository or from a live probe.
+	Fact Confidence = "fact"
+	// Inference is supported by evidence but was not verified directly.
+	Inference Confidence = "inference"
+	// Assumption is required because the evidence is missing.
+	Assumption Confidence = "assumption"
+)
+
+func (c Confidence) Valid() bool {
+	switch c {
+	case Fact, Inference, Assumption:
+		return true
+	}
+	return false
 }
 
+// Finding is one thing research established, with the evidence for it.
+//
+// ID is what makes a finding citable. A plan phase references "research:r12",
+// and the seal resolves that against the accepted research, so a plan cannot
+// rest on a finding nobody recorded. The advertised schema at agentctx.go
+// promised id and confidence for months while the struct dropped both.
+type Finding struct {
+	ID         string     `json:"id"`
+	Claim      string     `json:"claim"`
+	Evidence   string     `json:"evidence"`
+	Confidence Confidence `json:"confidence"`
+}
+
+// findingID is deliberately narrow. An id appears in plan prose as
+// "research:<id>", so anything with spaces or punctuation would make the
+// citation ambiguous to both a parser and a reader.
+var findingID = regexp.MustCompile(`^[a-z0-9][a-z0-9_-]{0,63}$`)
+
 // CodePath is a location the next phase will need, and why.
 type CodePath struct {
 	Path string `json:"path"`
@@ -68,7 +103,18 @@ func (r Research) Validate() error {
 	if err := bound("findings", len(r.Findings)); err != nil {
 		return err
 	}
+	seen := map[string]bool{}
 	for i, f := range r.Findings {
+		if !findingID.MatchString(f.ID) {
+			return fmt.Errorf("research: findings[%d].id %q must be lowercase letters, digits, dash or underscore, at most 64 characters", i, f.ID)
+		}
+		if seen[f.ID] {
+			return fmt.Errorf("research: duplicate finding id %q", f.ID)
+		}
+		seen[f.ID] = true
+		if !f.Confidence.Valid() {
+			return fmt.Errorf("research: findings[%d].confidence %q is not fact, inference, or assumption", i, f.Confidence)
+		}
 		if err := line(fmt.Sprintf("findings[%d].claim", i), f.Claim, true); err != nil {
 			return err
 		}
@@ -129,6 +175,9 @@ func Encode(v interface{ Validate() error }) ([]byte, error) {
 	return json.Marshal(v)
 }
 
+// DecodeResearch validates a newly sealed artifact. It is strict: a finding
+// without an id or a confidence is refused, and the refusal reaches the agent
+// that wrote it.
 func DecodeResearch(b []byte) (Research, error) {
 	var r Research
 	if err := json.Unmarshal(b, &r); err != nil {
@@ -137,6 +186,30 @@ func DecodeResearch(b []byte) (Research, error) {
 	return r, r.Validate()
 }
 
+// DecodeStoredResearch reads an artifact already in the CAS. Artifacts sealed
+// before ids existed carry neither field, and refusing them would block every
+// task whose research predates this change, including at rotation, where the
+// agent that could fix it is already gone.
+//
+// A backfilled finding is labelled inference: the old schema required
+// evidence and made no verification claim, so inference is what it actually
+// meant. Calling it fact would upgrade an unverified claim on the way in.
+func DecodeStoredResearch(b []byte) (Research, error) {
+	var r Research
+	if err := json.Unmarshal(b, &r); err != nil {
+		return Research{}, fmt.Errorf("research artifact: %w", err)
+	}
+	for i := range r.Findings {
+		if r.Findings[i].ID == "" {
+			r.Findings[i].ID = fmt.Sprintf("legacy-%d", i+1)
+		}
+		if r.Findings[i].Confidence == "" {
+			r.Findings[i].Confidence = Inference
+		}
+	}
+	return r, r.Validate()
+}
+
 func DecodePlan(b []byte) (Plan, error) {
 	var p Plan
 	if err := json.Unmarshal(b, &p); err != nil {
diff --git a/internal/workphase/workphase_test.go b/internal/workphase/workphase_test.go
index 0a524cc..fd6154c 100644
--- a/internal/workphase/workphase_test.go
+++ b/internal/workphase/workphase_test.go
@@ -7,7 +7,7 @@ import (
 
 func research() Research {
 	return Research{
-		Findings:   []Finding{{Claim: "attribution runs per figure", Evidence: "internal/attr/attr.go:88"}},
+		Findings:   []Finding{{ID: "r1", Confidence: Fact, Claim: "attribution runs per figure", Evidence: "internal/attr/attr.go:88"}},
 		Code:       []CodePath{{Path: "internal/attr/attr.go", Why: "aggregation happens here"}},
 		Invariants: []string{"identity semantics must not change"},
 		DeadEnds:   []DeadEnd{{Tried: "figure plurality", WhyFailed: "no measured gain"}},
@@ -59,7 +59,7 @@ func TestBoundsRejectUnboundedArtifacts(t *testing.T) {
 		"too many findings": func() error {
 			r := Research{}
 			for i := 0; i < 65; i++ {
-				r.Findings = append(r.Findings, Finding{Claim: "c", Evidence: "e"})
+				r.Findings = append(r.Findings, Finding{ID: "r1", Confidence: Fact, Claim: "c", Evidence: "e"})
 			}
 			return r.Validate()
 		},
@@ -99,3 +99,47 @@ func TestEncodeRejectsInvalid(t *testing.T) {
 		t.Fatal("Decode must reject non-JSON")
 	}
 }
+
+// The advertised schema promised findings[].id and findings[].confidence while
+// the struct carried neither, so both were dropped silently on every seal. A
+// plan cannot cite what was never stored.
+func TestFindingIdentityIsRequiredAndUnique(t *testing.T) {
+	cases := map[string]Research{
+		"no id":          {Findings: []Finding{{Confidence: Fact, Claim: "c", Evidence: "e"}}},
+		"upper case id":  {Findings: []Finding{{ID: "R1", Confidence: Fact, Claim: "c", Evidence: "e"}}},
+		"spaced id":      {Findings: []Finding{{ID: "r 1", Confidence: Fact, Claim: "c", Evidence: "e"}}},
+		"no confidence":  {Findings: []Finding{{ID: "r1", Claim: "c", Evidence: "e"}}},
+		"bad confidence": {Findings: []Finding{{ID: "r1", Confidence: "certain", Claim: "c", Evidence: "e"}}},
+		"duplicate id": {Findings: []Finding{
+			{ID: "r1", Confidence: Fact, Claim: "c", Evidence: "e"},
+			{ID: "r1", Confidence: Inference, Claim: "d", Evidence: "f"},
+		}},
+	}
+	for name, r := range cases {
+		if err := r.Validate(); err == nil {
+			t.Errorf("%s: accepted, want a refusal", name)
+		}
+	}
+}
+
+// Research sealed before ids existed must stay readable. Refusing it would
+// block every task whose research predates the change, including at rotation,
+// where the agent that could fix it is already gone.
+func TestStoredResearchWithoutIdentityStillDecodes(t *testing.T) {
+	legacy := []byte(`{"findings":[{"claim":"c","evidence":"e"},{"claim":"d","evidence":"f"}]}`)
+	if _, err := DecodeResearch(legacy); err == nil {
+		t.Fatal("a new seal without ids must be refused")
+	}
+	r, err := DecodeStoredResearch(legacy)
+	if err != nil {
+		t.Fatalf("stored decode: %v", err)
+	}
+	if r.Findings[0].ID != "legacy-1" || r.Findings[1].ID != "legacy-2" {
+		t.Fatalf("backfilled ids are not stable: %+v", r.Findings)
+	}
+	// Inference, not fact: the old schema required evidence and made no
+	// verification claim, so calling it fact would upgrade it on the way in.
+	if r.Findings[0].Confidence != Inference {
+		t.Fatalf("backfilled confidence is %q, want inference", r.Findings[0].Confidence)
+	}
+}