check-deck

check-deck is a skill for Claude Code, Codex from ginlix-ai/LangAlpha. It costs 22 tokens per session (629 once invoked), scanned A, original, Apache-2.0.

A quality check for investment banking presentations. It compares numbers, calculations, charts, claims, wording, time periods, units, and formatting across slides.

In plain words
What is it for?
Use it to audit revenue, EBITDA, valuation multiples, percentages, growth rates, chart directions, factual claims, and slide formatting in PowerPoint decks.
Why use it?
It catches inconsistencies between the data and the story before a presentation is shared with clients, boards, or investment committees.

Skill for Claude CodeCodex

About the project

LangAlpha is an agent workspace for researching financial markets and supporting investment decisions through persistent research, news analysis, and parallel subagents. It is for investors who want to develop and update trading theses over time, including generating long-short pair-trade ideas. The catalogue entries provide the skills, instructions, MCP servers, and plugin that make up its agent workflow.

ginlix-ai/LangAlpha · 1,722 stars · on GitHub

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 skills/ginlix-ai/langalpha/check-deck
Any agent
npx skills add ginlix-ai/LangAlpha --skill check-deck
Clone the repo
git clone --depth 1 https://github.com/ginlix-ai/LangAlpha

Made for: Claude Code, Codex.

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 check-deck

README.md
[![agentmods](https://agentmods.dev/badge/skills/ginlix-ai/langalpha/check-deck.svg)](https://agentmods.dev/skills/ginlix-ai/langalpha/check-deck)
Your own site
<a href="https://agentmods.dev/skills/ginlix-ai/langalpha/check-deck"><img src="https://agentmods.dev/badge/skills/ginlix-ai/langalpha/check-deck.svg" alt="Measured on agentmods" height="20"></a>
Per session 22 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 629 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 $0.00022 $0.00629
Opus 5 $0.00011 $0.00315
Sonnet 5 $0.00004 $0.00126
Haiku 4.5 $0.00002 $0.00063

Measured 5d ago against content hash 2482090eddf6, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

check-deck 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 5d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/extract_numbers.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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/langalpha_research/skills/check-deck/SKILL.md · 95 lines

How it starts

The opening of the file, as written. The whole thing — 95 lines — stays where its author put it; the contents beside it link to each section on GitHub.

IB Deck Checker

Perform comprehensive QC on investment banking presentations across four dimensions.

Prerequisites

Extract presentation content before checking:

python -m markitdown presentation.pptx > content.md

For visual inspection, convert to images using the pptx skill workflow.

Check Workflow

1. Number Consistency

Extract numbers with slide references:

python scripts/extract_numbers.py content.md --check

Verify:

  • Key metrics match across all slides (revenue, EBITDA, multiples)
  • Calculations are correct (totals, percentages, growth rates)
  • Units consistent (same scale used: millions vs billions, % vs bps)
  • Unit formatting consistent (e.g., $M vs $MM, $B vs $Bn - pick one style throughout)
  • Time periods aligned (FY vs LTM vs quarterly)

Flag pattern:

ISSUE: Revenue mismatch
- $500M on Slides 3, 8
- $485M on Slide 15 (DCF input)
ACTION: Reconcile figures

2. Data-Narrative Alignment

Map claims to supporting data:

  • Trend statements → chart directions
  • Market position claims → revenue/share data
  • Factual assertions → verify accuracy

Flag contradictions:

ISSUE: Narrative contradicts data
- Slide 4: "declining margins"
- Slide 7 chart: margins 18% → 22%
ACTION: Update narrative or verify data

Check plausibility (e.g., "#1 player in $100B market" with $200M revenue = 0.2% share).

3. Language Polish

Scan for:

  • Casual phrasing ("pretty good", "a lot of")
  • Vague quantifiers without specifics
  • Contractions, exclamation points
  • Inconsistent terminology

See references/ib-terminology.md for replacement patterns.

Flag pattern:

ISSUE: Casual language (Slide 12)
- "This deal is a no-brainer"
→ "The transaction presents a compelling value proposition"

4. Formatting QC

Audit each slide for:

  • Charts: Source citations, axis labels, legends
  • Typography: Consistent fonts, size hierarchy
  • Numbers: Consistent formatting (1,000 vs 1K)
  • Dates: Consistent format throughout
  • Footnotes: Proper sourcing and disclaimers

Read the full file on GitHub · 95 lines

Files

What ships with it

3 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. 5d ago First seen · 95 lines · 22 tokens per session scan A 2482090eddf6

Subscribe to this mod's changes

check-deck is a skill published in the GitHub repository ginlix-ai/LangAlpha (1,722 stars, last pushed today), licensed Apache-2.0. It adds 22 tokens to every session and 629 once invoked, about $0.0001 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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