diff --git a/agents/analyze_agent_v2/skills/mobius_error_id_skill/SKILL.md b/agents/analyze_agent_v2/skills/mobius_error_id_skill/SKILL.md
index 8a5d048..98ee03e 100644
--- a/agents/analyze_agent_v2/skills/mobius_error_id_skill/SKILL.md
+++ b/agents/analyze_agent_v2/skills/mobius_error_id_skill/SKILL.md
@@ -1,20 +1,29 @@
 ---
 name: mobius-error-id-skill
-description: Interpret Mobius error and call IDs from logs using the reference documentation.
+description: "Decode Mobius error codes (mobius-error 101–5xx), trace call IDs, and map HTTP response statuses to root causes in Mobius logs. Use when analyzing Mobius log output containing error codes, response_status fields, call IDs, or registration/call failures and the user needs help debugging or understanding them."
 ---
 
 # Mobius Error ID Lookup
 
-When analyzing Mobius logs, use this skill to interpret error IDs and call-related identifiers.
+When analyzing Mobius logs, use this skill to decode error codes, trace call IDs to root causes, and map error patterns to known issues.
 
-## Instructions
+## Error ID Formats
 
-1. **Identify Mobius error IDs and call IDs** in the logs you are analyzing (e.g. from `mobius_logs`, or any field containing Mobius error codes, call IDs, or tracking identifiers that map to known error semantics).
+Mobius errors appear in logs as:
+- **HTTP status + mobius-error code**: `403 FORBIDDEN — mobius-error 101` (registration), `503 SERVICE UNAVAILABLE` (transient backend failure)
+- **response_status fields**: `fields.response_status: 503`, `fields.response_status: 404`
+- **Call/device IDs**: `deviceId`, `sipCallId`, `USER_ID`, `DEVICE_ID` — used to correlate across services
 
-2. **Consult the reference document** `references/mobius_error_ids.md` to look up each such ID. That document contains the authoritative mapping of Mobius error/call IDs to their meanings, causes, and remediation notes.
+## Workflow
 
-3. **Include the interpretation in your analysis:**
-   - In **Error Detection and Root Cause Analysis**: For each Mobius error ID found, state what the ID means (from the reference), likely cause, and suggested fix.
-   - In **Root Cause Analysis** (if applicable): Reference the documentation so your explanation is consistent with the defined semantics of each ID.
+1. **Extract error identifiers** from the logs — look for `mobius-error` codes, HTTP status codes in `response_status` fields, and call/device IDs (`deviceId`, `sipCallId`, `correlationId`).
 
-4. If an ID is not present in the reference document, say so and describe the ID and context so a human can triage or update the documentation.
+2. **Look up each error** in `references/mobius_error_ids.md`. For each match, note the meaning, user/call impact, root cause direction, and what to check next.
+
+3. **Include findings in your analysis**: For each error ID, state what it means, the likely cause, the affected dependency (SSE, CPAPI, Redis, CI), and suggested next steps.
+
+4. **If an ID is not in the reference**, say so and describe the ID, surrounding context, and log fields so a human can triage or update the documentation.
+
+## Example
+
+A log line shows `Registration: Error code: 503 SERVICE UNAVAILABLE` with message `"No more retries left, failed to setup connection with all remote hosts"`. Look up **503 SERVICE UNAVAILABLE (registration)** in the reference — this means Mobius tried all SSE nodes and failed to connect. Root cause: SSE cluster or network issue. Next step: check SSE health and network path in the same time window.