⌘
Context Lens
v1.0.8🛡️Tier 1 Security AuditedCLI v2.1.287+ VerifiedInteractive token distribution breakdown by system instructions, MCP tools, and codebase buffers.
⚡Installation Specifier
$/plugin install context-lens@marketplace
Problem Solved & Architectural Motivation
Renders an interactive terminal breakdown showing exact token percentages consumed by system prompts, MCP tool schemas, conversation history, and project files. Alerts when prompt caching expires.
Before Execution
Zero-Time AST Interception
Evaluates tool payloads prior to kernel fork.
Scoring Model
0-100 Impact Index
Weighted heuristic scoring: files touched, git dirty state, env scope.
Non-Intrusive
Native CLI Hook
Zero proxy daemon required; hooks straight into Claude tool calls.
Lifecycle Architecture & Hook Flow
Step 01
Claude Plan
Prompt Inference
Step 02
Tool Call
tool.call Payload
HOOK INTERCEPT
context-lens
<18ms Heuristic
Step 04
OS Execution
Kernel Fork
Manifest Schema (plugin.json)
{
"name": "context-lens",
"version": "1.0.8"
}Hook Implementation (register.js)
export default function setup(lens) {
lens.on('turn.before', (metrics) => {
lens.ui.printContextBar({
system: metrics.systemTokens,
tools: metrics.mcpTokens,
user: metrics.conversationTokens
});
});
}Security Audit95/100
Network EgressNone (Zero Socket Egress)
Filesystem ScopeBounded to Workspace
Credential Exposure0 Leaks Detected
Sandbox IsolationHost User Privilege
Technical Specifications
Min CLI Versionv2.1.287+
Categorycontext-usage
Runtime Overhead< 18ms AST
LicenseMIT
Mod Publisher
@P
prompt-metrics
github.com/prompt-metrics ↗