diff --git a/heicode/controller/heicode_config.go b/heicode/controller/heicode_config.go
index 30329bcc..367851f6 100644
--- a/heicode/controller/heicode_config.go
+++ b/heicode/controller/heicode_config.go
@@ -24,6 +24,8 @@ func HeicodeConfig(c *gin.Context) {
 			"endpoint":           "/api/heicode/telemetry/events",
 			"max_batch":          common.GetEnvOrDefault("HEICODE_TELEMETRY_MAX_BATCH", telemetryMaxBatch),
 			"flush_interval_sec": common.GetEnvOrDefault("HEICODE_TELEMETRY_FLUSH_INTERVAL_SEC", 30),
+			// Server retention window (#32): events older than this are purged.
+			"retention_days": telemetryRetentionDays(),
 		},
 	})
 }
diff --git a/heicode/controller/heicode_telemetry.go b/heicode/controller/heicode_telemetry.go
index 00956665..a64b0736 100644
--- a/heicode/controller/heicode_telemetry.go
+++ b/heicode/controller/heicode_telemetry.go
@@ -25,8 +25,65 @@ const (
 	telemetryMaxBatch    = 20
 	telemetryMaxBodySize = 256 * 1024
 	headerDeviceID       = "X-Heicode-Device-Id"
+	// Per-field hard cap after redaction (#32): a backstop so a single event
+	// can't park an unbounded blob in the telemetry store even within batch
+	// limits. stack_top / context are truncated past this many bytes.
+	telemetryMaxFieldBytes = 8 * 1024
 )
 
+// telemetryContextAllowedKeys whitelists the non-content diagnostic keys the
+// client may attach to an event's `context` (#32). Anything else is dropped
+// before persistence, so a client regression can't land arbitrary — possibly
+// identifying — JSON (prompts, code, tokens, emails, full file paths, raw IPs)
+// in the telemetry store. Keep in sync with the client telemetry contract
+// (winos#23) and docs/integration/heicode-desktop-client-api.md. Additions must
+// be reviewed against the "no identifying content" rule in issue #32.
+var telemetryContextAllowedKeys = map[string]bool{
+	"route":       true, // logical UI route, e.g. "chat" (no params)
+	"retryable":   true, // bool
+	"phase":       true, // lifecycle phase enum
+	"exit_code":   true, // process exit code (int)
+	"duration_ms": true, // numeric timing
+	"attempt":     true, // retry attempt count
+}
+
+// filterTelemetryContext keeps only whitelisted keys from the client-supplied
+// context object, then redacts and size-caps the result (#32). Returns "" when
+// the context is empty, unparseable, or has no allowed keys — telemetry is
+// best-effort diagnostics, so dropping an unrecognized payload is preferable to
+// storing arbitrary JSON.
+func filterTelemetryContext(raw json.RawMessage) string {
+	if len(raw) == 0 {
+		return ""
+	}
+	var obj map[string]json.RawMessage
+	if err := common.Unmarshal(raw, &obj); err != nil {
+		return "" // not an object (or malformed) -> drop
+	}
+	filtered := make(map[string]json.RawMessage, len(obj))
+	for k, v := range obj {
+		if telemetryContextAllowedKeys[k] {
+			filtered[k] = v
+		}
+	}
+	if len(filtered) == 0 {
+		return ""
+	}
+	b, err := common.Marshal(filtered)
+	if err != nil {
+		return ""
+	}
+	return capTelemetryField(model.RedactText(string(b)))
+}
+
+// capTelemetryField truncates an already-redacted field to telemetryMaxFieldBytes.
+func capTelemetryField(s string) string {
+	if len(s) <= telemetryMaxFieldBytes {
+		return s
+	}
+	return s[:telemetryMaxFieldBytes]
+}
+
 type telemetryEventIn struct {
 	ClientId         string          `json:"client_id"`
 	SchemaVersion    int             `json:"schema_version"`
@@ -73,13 +130,12 @@ func (e telemetryEventIn) toModel(userID int, deviceID string, now int64) model.
 	stackTopJSON := ""
 	if len(e.StackTop) > 0 {
 		if b, err := common.Marshal(e.StackTop); err == nil {
-			stackTopJSON = model.RedactText(string(b))
+			stackTopJSON = capTelemetryField(model.RedactText(string(b)))
 		}
 	}
-	ctxJSON := ""
-	if len(e.Context) > 0 {
-		ctxJSON = model.RedactText(string(e.Context))
-	}
+	// #32: context is restricted to a key whitelist (drop arbitrary/identifying
+	// JSON), then redacted and size-capped.
+	ctxJSON := filterTelemetryContext(e.Context)
 	return model.TelemetryEvent{
 		ReceivedAt:       now,
 		UserId:           userID,
diff --git a/heicode/controller/heicode_telemetry_test.go b/heicode/controller/heicode_telemetry_test.go
index b9dec944..aa9f0535 100644
--- a/heicode/controller/heicode_telemetry_test.go
+++ b/heicode/controller/heicode_telemetry_test.go
@@ -65,12 +65,45 @@ func TestTelemetryToModel_RedactsSecrets(t *testing.T) {
 	ev := telemetryEventIn{
 		ClientId: "dev-1",
 		StackTop: []string{"at boom (auth.ts) key=sk-abcDEF1234567890"},
-		Context:  json.RawMessage(`{"hdr":"Authorization: Bearer aZ09tokenVALUE","ok":true}`),
+		// "route" is whitelisted (#32) so it survives the field filter; redaction
+		// must still strip the Bearer token carried inside an allowed key.
+		Context: json.RawMessage(`{"route":"Authorization: Bearer aZ09tokenVALUE","retryable":true}`),
 	}
 	m := ev.toModel(7, "dev-1", 1700000000)
 
 	require.NotContains(t, m.StackTopJSON, "sk-abcDEF1234567890", "sk- secret must be redacted in stack_top")
 	require.Contains(t, m.StackTopJSON, "REDACTED")
 	require.NotContains(t, m.ContextJSON, "aZ09tokenVALUE", "Bearer token must be redacted in context")
-	require.Contains(t, m.ContextJSON, "ok") // non-secret content preserved
+	require.Contains(t, m.ContextJSON, "retryable") // non-secret whitelisted content preserved
+}
+
+// #32: context must be restricted to a key whitelist so a client regression
+// cannot land arbitrary/identifying JSON in the telemetry store.
+func TestFilterTelemetryContext_Whitelist(t *testing.T) {
+	// allowed keys kept, unknown keys (incl. potentially identifying) dropped
+	out := filterTelemetryContext(json.RawMessage(
+		`{"route":"chat","retryable":true,"email":"a@b.com","file":"C:/Users/x/secret.go","prompt":"hi"}`))
+	require.Contains(t, out, "route")
+	require.Contains(t, out, "retryable")
+	require.NotContains(t, out, "email")
+	require.NotContains(t, out, "a@b.com")
+	require.NotContains(t, out, "secret.go")
+	require.NotContains(t, out, "prompt")
+
+	// no allowed keys -> dropped entirely
+	require.Equal(t, "", filterTelemetryContext(json.RawMessage(`{"email":"a@b.com"}`)))
+	// non-object / malformed -> dropped
+	require.Equal(t, "", filterTelemetryContext(json.RawMessage(`"a string"`)))
+	require.Equal(t, "", filterTelemetryContext(json.RawMessage(`not json`)))
+	require.Equal(t, "", filterTelemetryContext(nil))
+}
+
+// #32: per-field size cap is a backstop against unbounded blobs.
+func TestCapTelemetryField(t *testing.T) {
+	require.Equal(t, "short", capTelemetryField("short"))
+	big := make([]byte, telemetryMaxFieldBytes+100)
+	for i := range big {
+		big[i] = 'a'
+	}
+	require.Len(t, capTelemetryField(string(big)), telemetryMaxFieldBytes)
 }
diff --git a/heicode/controller/telemetry_retention.go b/heicode/controller/telemetry_retention.go
new file mode 100644
index 00000000..5601b1ab
--- /dev/null
+++ b/heicode/controller/telemetry_retention.go
@@ -0,0 +1,77 @@
+package controller
+
+import (
+	"fmt"
+	"sync"
+	"time"
+
+	"github.com/heicode/manager/common"
+	"github.com/heicode/manager/model"
+)
+
+// Telemetry retention (#32). Account-linkable client error-telemetry must not be
+// kept indefinitely: a daily task deletes rows older than the retention window.
+// Disabled when telemetry ingest is off (default) or retention <= 0.
+//
+//   - HEICODE_TELEMETRY_RETENTION_DAYS (default 30): rows received earlier than
+//     now-RETENTION are deleted. <=0 disables the purge (keep-forever — only for
+//     explicit operator opt-out; not recommended for production).
+//   - HEICODE_TELEMETRY_RETENTION_INTERVAL_HOURS (default 24): sweep cadence.
+//
+// Master-only (wired from main.go under IsMasterNode) so multiple nodes don't
+// all sweep the shared LOG_DB.
+
+var telemetryRetentionTaskOnce sync.Once
+
+func telemetryRetentionDays() int {
+	return common.GetEnvOrDefault("HEICODE_TELEMETRY_RETENTION_DAYS", 30)
+}
+
+// StartTelemetryRetentionTask launches the daily telemetry retention sweep.
+func StartTelemetryRetentionTask() {
+	telemetryRetentionTaskOnce.Do(func() {
+		// Only meaningful once ingest is enabled; if the endpoint is off there is
+		// nothing being written, but we still allow the sweep to drain any rows
+		// captured during a prior enabled window. Gate on retention days instead.
+		days := telemetryRetentionDays()
+		if days <= 0 {
+			common.SysLog("telemetry retention task disabled (HEICODE_TELEMETRY_RETENTION_DAYS<=0; rows kept indefinitely)")
+			return
+		}
+		intervalHours := common.GetEnvOrDefault("HEICODE_TELEMETRY_RETENTION_INTERVAL_HOURS", 24)
+		if intervalHours < 1 {
+			intervalHours = 24
+		}
+		go func() {
+			time.Sleep(5 * time.Minute) // avoid startup churn
+			runTelemetryRetentionOnce()
+			ticker := time.NewTicker(time.Duration(intervalHours) * time.Hour)
+			defer ticker.Stop()
+			for range ticker.C {
+				runTelemetryRetentionOnce()
+			}
+		}()
+		common.SysLog(fmt.Sprintf("telemetry retention task started: retention=%dd interval=%dh", days, intervalHours))
+	})
+}
+
+func runTelemetryRetentionOnce() {
+	defer func() {
+		if r := recover(); r != nil {
+			common.SysLog(fmt.Sprintf("telemetry retention task panic recovered: %v", r))
+		}
+	}()
+	days := telemetryRetentionDays()
+	if days <= 0 {
+		return
+	}
+	cutoff := time.Now().Unix() - int64(days)*86400
+	deleted, err := model.DeleteTelemetryEventsBefore(cutoff)
+	if err != nil {
+		common.SysLog("telemetry retention task: " + err.Error())
+		return
+	}
+	if deleted > 0 {
+		common.SysLog(fmt.Sprintf("telemetry retention task: deleted %d events older than %d days", deleted, days))
+	}
+}
diff --git a/heicode/main.go b/heicode/main.go
index 77812f70..3b04573f 100644
--- a/heicode/main.go
+++ b/heicode/main.go
@@ -134,6 +134,9 @@ func main() {
 	// retention window (issue #4). Master-only so multiple nodes don't all purge.
 	if common.IsMasterNode {
 		controller.StartSecretPurgeTask()
+		// Telemetry retention: daily purge of client error-telemetry older than
+		// HEICODE_TELEMETRY_RETENTION_DAYS (#32). Master-only.
+		controller.StartTelemetryRetentionTask()
 	}
 
 	if common.IsMasterNode && constant.UpdateTask {
diff --git a/heicode/model/telemetry_event.go b/heicode/model/telemetry_event.go
index c7e23c13..65fac5ce 100644
--- a/heicode/model/telemetry_event.go
+++ b/heicode/model/telemetry_event.go
@@ -39,3 +39,15 @@ func InsertTelemetryEvents(events []TelemetryEvent) error {
 	}
 	return LOG_DB.Create(&events).Error
 }
+
+// DeleteTelemetryEventsBefore removes telemetry rows received before cutoffUnix
+// (server unix seconds), enforcing the retention window (#32). Returns the
+// number of rows deleted. Account-linkable device telemetry must not be kept
+// indefinitely; callers run this from a periodic retention task.
+func DeleteTelemetryEventsBefore(cutoffUnix int64) (int64, error) {
+	if LOG_DB == nil {
+		return 0, nil
+	}
+	res := LOG_DB.Where("received_at < ?", cutoffUnix).Delete(&TelemetryEvent{})
+	return res.RowsAffected, res.Error
+}