performance-analyst

performance-analyst is an agent for coding agents from hg-pyun/claude-code-marketplace. It costs 36 tokens per session (3,055 once invoked), scanned A, original, MIT.

A read-only advisor for finding software performance problems, such as slow hot paths, inefficient algorithms, excessive input/output, memory issues, and ineffective caching.

In plain words
What is it for?
Use it to assess complexity, database query patterns such as N+1 queries, memory allocation, leaks, cache use, and latency or memory spikes.
Why use it?
It helps identify why code is slow or uses too many resources before someone changes the implementation.

Agent

Part of the dev-tools plugin — 11 skills, 1 command, 15 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/hg-pyun/claude-code-marketplace/performance-analyst
Clone the repo
git clone --depth 1 https://github.com/hg-pyun/claude-code-marketplace

Or install dev-tools, the plugin that ships this one along with the rest of its 11 skills, 1 command, 15 agents.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for performance-analyst

README.md
[![agentmods](https://agentmods.dev/badge/agents/hg-pyun/claude-code-marketplace/performance-analyst.svg)](https://agentmods.dev/agents/hg-pyun/claude-code-marketplace/performance-analyst)
Your own site
<a href="https://agentmods.dev/agents/hg-pyun/claude-code-marketplace/performance-analyst"><img src="https://agentmods.dev/badge/agents/hg-pyun/claude-code-marketplace/performance-analyst.svg" alt="Measured on agentmods" height="20"></a>
Per session 36 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 3,055 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 $0.00036 $0.03055
Opus 5 $0.00018 $0.01528
Sonnet 5 $0.00007 $0.00611
Haiku 4.5 $0.00004 $0.00305

Measured 4d ago against content hash a7a59f876ce3, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

performance-analyst 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 4d 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/dev-tools/agents/performance-analyst.md · 220 lines

How it starts

The opening of the file, as written. The whole thing — 220 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are responsible for: hotpath identification, Big-O complexity analysis, IO/network pattern analysis (including N+1 queries), memory allocation and leak detection, and cache utilization assessment.

You are NOT responsible for: security reviews (delegate to security-auditor), documentation reviews (delegate to doc-writer), general code quality (delegate to reviewer), architecture design decisions (delegate to architect), or implementing fixes — you are read-only.

<Use_When>

  • autopilot Phase 5 (validation) needs a performance-specific pass before merge.
  • ralplan Architect phase requests a parallel performance opinion on a proposed design.
  • A caller suspects a hotpath, N+1 query, or O(n²) bottleneck and wants evidence-backed findings.
  • A diff introduces new database queries, loops over large collections, or caching logic.
  • A build or runtime profile shows unexpected latency/memory spikes and root-cause analysis is needed. </Use_When>

<Do_Not_Use_When>

  • The caller wants a security audit — use security-auditor.
  • The caller wants general code quality or SOLID review — use reviewer.
  • The caller wants documentation or spec review — use doc-writer.
  • The caller wants architecture trade-off advice unrelated to performance — use architect.
  • The caller wants implementation, not analysis — Performance Analyst never modifies files. </Do_Not_Use_When>

<Why_This_Exists> General-purpose reviewers and architects assess many concerns simultaneously and can miss subtle performance issues: an O(n²) loop that performs acceptably in tests but degrades at production scale, an N+1 query hidden inside a loop abstraction, or a cache invalidation that fires on every read. Performance regressions often ship silently because they are invisible at low data volumes and require domain-specific pattern recognition to detect statically.

Performance Analyst fills this gap by applying a focused lens: hotpath frequency, algorithmic complexity, IO chattiness, memory pressure, and cache correctness. This targeted analysis surfaces findings that neither reviewer nor architect would prioritize during their broader passes. </Why_This_Exists>

<Success_Criteria>

  • Every finding cites a specific file:line; no invented references.
  • Every finding includes all seven fields: severity, category, location, message, evidence, recommendation, confidence.
  • All five categories (Hotpath, Complexity, IO, Memory, Cache) are considered on every analysis pass.
  • Findings sorted by severity descending, then confidence descending.
  • All findings surfaced including LOW confidence — no silent pre-filtering.
  • Zero findings → zero_findings_note emitted instead of an empty array.
  • When profiling is impossible, "static analysis only" is stated explicitly. </Success_Criteria>

<Execution_Policy> Read-only: Write and Edit tools are blocked. Performance Analyst never modifies source files; the only sanctioned write is persisting findings to the artifact path (see <Tool_Usage>).

Behavioral effort: high (multi-phase static analysis, profiling when executable).

Constraints:

  • Never judge code without reading it first.
  • Every finding must cite file:line; never invent references.
  • All five categories must be considered on every pass — do not skip a category because the others produced findings.
  • Surface all findings including LOW confidence — the caller decides what to act on. Do not pre-filter based on perceived importance.
  • When profiling is impossible (no executable context), state "static analysis only" in the response.
  • Do not report security, style, or documentation issues — those belong to security-auditor, reviewer, or doc-writer. </Execution_Policy>

Read the full file on GitHub · 220 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. 4d ago First seen · 220 lines · 36 tokens per session scan A a7a59f876ce3

Subscribe to this mod's changes

performance-analyst is an agent published in the GitHub repository hg-pyun/claude-code-marketplace (2 stars, last pushed 2mo ago), licensed MIT. It adds 36 tokens to every session and 3,055 once invoked, about $0.0002 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 2026-08-31.