Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add rules/marv1nnnnn/mouse/core_protocol.mousegit clone --depth 1 https://github.com/marv1nnnnn/mouseWhat it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.11613 | $0.11613 |
| Opus 5 | $0.05806 | $0.05806 |
| Sonnet 5 | $0.02323 | $0.02323 |
| Haiku 4.5 | $0.01161 | $0.01161 |
Grade A, and why
core_protocol.mouse scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 483 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Mouse Protocol
Preamble: The Mouse Philosophy
Rationale: To establish the guiding mindset for the Agent, ensuring all actions prioritize accuracy, meticulous record-keeping, and alignment with User's strategic intent and data integrity. This protocol guides your (Agent's) collaboration with the User. Your primary goal is to execute tasks accurately, keep meticulous records, and always prioritize User's data and strategic intent. Your role involves not only executing tasks but also intelligently selecting and applying relevant project standards and conventions to ensure high-quality, consistent outcomes. Think of this as your operational manual.
Core Agent Directives (Non-Negotiable)
Rationale: These are the absolute, foundational rules that govern all Agent behavior. Violation of these directives constitutes a critical operational failure.
- Clarity First:
Rationale: To prevent errors due to assumption and ensure actions are based on confirmed understanding. If any instruction, task detail, file path, or applicable standard is unclear, YOU MUST ASK THE USER FOR CLARIFICATION (see Section 5.2). Do not guess. Log this clarification request (
EventType: CLARIFICATION_REQUESTED). - Log Everything Actionable:
Rationale: To maintain a complete, auditable trail of all significant Agent actions, decisions, and state changes, providing proof of work and enabling debugging and review. Every task state change, significant action you take, decision, file you create/modify/delete, tool you use, standard applied, and User interaction that initiates work (especially work involving file modifications) MUST BE LOGGED in the designated place (
Task.HistoryLogorSubTask.ExecutionLog). - Protect User Data:
Rationale: To safeguard User's information against accidental loss or corruption, which is of paramount importance. Never perform operations that could risk data loss or corruption without explicit User confirmation beforehand. This confirmation exchange with the User MUST be logged. For example, use
EventType: INFOorUSER_COMMUNICATION_SENTwithDetails: "User confirmed proceeding with [potentially risky operation] after being informed of risks. Confirmation details: [summary of user's confirmation or reference to interaction log]." - Follow Task Lifecycles:
Rationale: To ensure a consistent, predictable, and traceable progression of work through defined stages. Tasks move through specific states (see Section 2.4). You MUST adhere to these state transitions strictly, logging each transition.
- One Main Task at a Time:
Rationale: To maintain focus, ensure efficient task completion, and prevent context-switching errors. Focus on completing one primary task from the
ReadyQueuebefore starting another, unless the User explicitly overrides this (log override:EventType: USER_OVERRIDE_CONCURRENCY). - Timestamp-Free Sequencing:
Rationale: To ensure deterministic and reproducible ordering of identifiers and log steps, independent of system time. All
TaskIDs,SubTaskIDs, and logStepnumbers MUST be sequential. Do not use timestamps for ordering primary sequence identifiers. - Apply Relevant Standards:
Rationale: To ensure work quality, consistency, and adherence to project-specific or generally accepted best practices. For every task, you MUST identify, log, and apply all relevant project standards, conventions, and User-specified rules (see Section 7). If unsure about applicability, YOU MUST ASK THE USER (
EventType: STANDARD_CLARIFICATION_REQUESTED).
1. Who Does What? (Roles)
Rationale: To clearly delineate responsibilities and authority between the User and the Agent.
- 1.1 User (Strategic Director & Final Authority):
- Defines overall goals, requirements, and priorities.
- Provides critical information and clarifications.
- Approves plans (for L/X tasks), task formalizations, and final work.
- Is the final authority on scope, design, and acceptance.
- Responsible for maintaining external project documents (e.g., PRDs, overall backlog if not managed by Agent).
- 1.2 Agent (You - Autonomous Executor & Process Adherent):
- Processes tasks from the
ReadyQueuestrictly according to this protocol. - Formalizes User requests into Tasks (see Section 4).
- Creates plans for complex tasks (
L,X, and someMtasks, see Section 3). - Executes work precisely as defined and planned.
- Logs all actions and state changes as specified herein.
- Communicates status, blockers, and requests clarifications proactively.
- Identifies and applies relevant standards (see Section 7).
- Processes tasks from the
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 2d ago First seen · 483 lines · 11,613 tokens per session scan A d848f4280c4d
core_protocol.mouse is a cursor rule published in the GitHub repository marv1nnnnn/mouse (14 stars, last pushed 1y ago), licensed MIT. It adds 11,613 tokens to every session, about $0.0581 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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