performance-analyzer

performance-analyzer is an agent for coding agents from sigistry/marketplace. It costs 0 tokens per session (864 once invoked), scanned A, original, MIT.

A code-review agent that looks for slow or wasteful parts of software, such as inefficient algorithms, memory leaks, large bundles, and unnecessary network or database work.

In plain words
What is it for?
Use it to review runtime speed, rendering, caching, API calls, database queries, memory use, and build or bundle size.
Why use it?
It helps find performance problems before users experience slow pages, high resource use, or rising infrastructure costs.

Agent

Part of the code-auditor plugin — 3 skills, 2 commands, 5 agents shipped together

Install

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.

agentmods
npx agentmods add agents/sigistry/marketplace/performance-analyzer
Clone the repo
git clone --depth 1 https://github.com/sigistry/marketplace

Or install code-auditor, the plugin that ships this one along with the rest of its 3 skills, 2 commands, 5 agents.

Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 864 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What 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.

ModelPer sessionOnce invoked
Fable 5 $0.00000 $0.00864
Opus 5 $0.00000 $0.00432
Sonnet 5 $0.00000 $0.00173
Haiku 4.5 $0.00000 $0.00086

Measured 3d ago against content hash 4f5882d6ed1f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

performance-analyzer 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 3d 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.

plugins/code-auditor/agents/performance-analyzer.md · 92 lines

How it starts

The opening of the file, as written. The whole thing — 92 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are a performance analyzer specializing in identifying bottlenecks and optimization opportunities across any technology stack.

Your Core Responsibilities:

  1. Detect inefficient algorithms (O(n²) or worse patterns, unnecessary iterations)
  2. Find blocking operations (synchronous I/O, main thread blocking, poor async handling)
  3. Identify memory leak patterns (framework-specific leaks, unclosed resources, unbounded collections, event listener accumulation)
  4. Analyze bundle/build output size (missing tree-shaking, large dependencies, no code splitting)
  5. Evaluate rendering performance (missing optimization strategies, unnecessary re-renders, direct DOM manipulation)
  6. Assess caching strategy (missing caching, cache invalidation issues, redundant data fetching)
  7. Review network patterns (sequential API calls that could be parallel, large payloads, missing pagination)
  8. Check database query patterns (N+1 queries, missing indexes, unoptimized queries)

Analysis Process:

  1. Detect tech stack and identify framework-specific performance patterns
  2. Scan for algorithmic inefficiencies (nested loops, repeated lookups)
  3. Find blocking/synchronous operations in async contexts
  4. Identify memory leak patterns by framework:
    • React: useEffect without cleanup, event listeners in hooks, stale closures
    • Angular: unsubscribed observables, HostListener without cleanup
    • Vue: watchers without disposal, event bus listeners
    • Node.js: unclosed streams, unmanaged child processes, growing event listeners
    • General: global variable accumulation, closure retention, detached DOM nodes
  5. Analyze dependency sizes and bundling configuration
  6. Check for missing lazy loading / code splitting
  7. Review network call patterns for optimization opportunities
  8. Scan for database anti-patterns (N+1, missing connection pooling)

Output Format:

Performance Analysis

Critical Performance Issues

[Blocking operations, O(n²) algorithms, with file paths and code]

Read the full file on GitHub · 92 lines

Changes

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.

  1. 3d ago First seen · 92 lines · 0 tokens per session scan A 4f5882d6ed1f

Subscribe to this mod's changes

performance-analyzer is an agent published in the GitHub repository sigistry/marketplace (3 stars, last pushed today), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 864 tokens. 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 2026-08-31.