- name
- context-sentinel
- description
- Monitors session context and automatically manages model switching based on a cascading protocol. Use as part of a heartbeat or cron job to maintain session health and optimize token usage.
- version
- 1.0.0
Context Sentinel
This skill provides a script to automate the "Cascading Model Protocol," ensuring the agent gracefully degrades from high-cost models to high-context models as the session grows.
Protocol Summary
- Opus 4.6: Use until 80% context, then switch to Opus 4.5.
- Opus 4.5: Use until 80% context, then switch to Gemini 2.5 Pro.
- Gemini Pro: Use until 80% context, then trigger a handoff.
This skill operationalizes the logic defined in MEMORY.md.
How to Use
This skill is designed to be run periodically, either via a cron job or as part of the main agent's HEARTBEAT.md checklist.
Workflow
- Execute the script:
Run the check_context.ps1 script to get the current session status and determine the required action.
powershell -File scripts/check_context.ps1- Evaluate the output:
The script will return one of three possible string commands: * SWITCH_TO:<model_id> * HANDOFF_NOW * STATUS_OK
- Take Action:
Based on the output, execute the appropriate agent command.
* If SWITCH_TO:<model_id>, run session_status with the new model ID:
session_status model=<model_id>* If HANDOFF_NOW, trigger the handoff process by writing to the handoff file. This is typically done by running a specific, pre-defined prompt or script.
* If STATUS_OK, no action is needed.
Example Usage in HEARTBEAT.md
You can replace the manual checks in your HEARTBEAT.md with a call to this skill's script.
Old HEARTBEAT.md:
## Cascading Model Protocol (Check Every Heartbeat)
1. **Check Status:** Get current model and context %.
2. **Opus 4.6:** If model is `Opus 4.6` and context > 80% -> Switch to `Opus 4.5`.
...New HEARTBEAT.md using this skill:
## Context Sentinel (Check Every Heartbeat)
1. Run `powershell -File skills/context-sentinel/scripts/check_context.ps1`.
2. Evaluate the output and take action (`SWITCH_TO`, `HANDOFF_NOW`, or `STATUS_OK`).This makes the logic reusable and keeps the HEARTBEAT.md file clean and focused on execution.