Cre Industrial
ahacker-1/cre-agent-skills
CRE Industrial analysis suite - 8 specialist skills for U.S.
Reason like a master builder — one mind holding an entire built-asset project from raw land through design, construction, handover, operations, and disposition, anywhere in the world.
Install Master Builder
$ npx skills add ibuilder/massing --skill master-builder -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install ibuilder/massing master-builder --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/ibuilder/massing.git skills-src && mkdir -p .claude/skills && cp -r skills-src/.claude/skills/master-builder .claude/skills/master-builder && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "master-builder" agent skill from https://github.com/ibuilder/massing/tree/main/.claude/skills/master-builder into .claude/skills/master-builder/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "master-builder", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/ibuilder/massing/tree/main/.claude/skills/master-builderType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add ibuilder/massing --skill master-builder -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install ibuilder/massing master-builder --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/ibuilder/massing.git skills-src && mkdir -p .agents/skills && cp -r skills-src/.claude/skills/master-builder .agents/skills/master-builder && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "master-builder" agent skill from https://github.com/ibuilder/massing/tree/main/.claude/skills/master-builder into .agents/skills/master-builder/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "master-builder", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add ibuilder/massing --skill master-builder -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install ibuilder/massing master-builder --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/ibuilder/massing.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/.claude/skills/master-builder .cursor/skills/master-builder && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "master-builder" agent skill from https://github.com/ibuilder/massing/tree/main/.claude/skills/master-builder into .cursor/skills/master-builder/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "master-builder", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/ibuilder/massing.git --path .claude/skills/master-builder--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add ibuilder/massing --skill master-builder -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install ibuilder/massing master-builder --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/ibuilder/massing.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/.claude/skills/master-builder .gemini/skills/master-builder && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "master-builder" agent skill from https://github.com/ibuilder/massing/tree/main/.claude/skills/master-builder into .gemini/skills/master-builder/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "master-builder", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install ibuilder/massing master-builderInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add ibuilder/massing --skill master-builder -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/ibuilder/massing.git skills-src && mkdir -p .github/skills && cp -r skills-src/.claude/skills/master-builder .github/skills/master-builder && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "master-builder" agent skill from https://github.com/ibuilder/massing/tree/main/.claude/skills/master-builder into .github/skills/master-builder/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "master-builder", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add ibuilder/massing --skill master-builder -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install ibuilder/massing master-builder --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/ibuilder/massing.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/.claude/skills/master-builder .opencode/skills/master-builder && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "master-builder" agent skill from https://github.com/ibuilder/massing/tree/main/.claude/skills/master-builder into .opencode/skills/master-builder/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "master-builder", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
Facts
- Skill name
master-builder- GitHub stars
- 121
- Token cost
- ~2.6k tokens
- SKILL.md length
- 1,311 words
- Files
- 9 (incl. references)
- Skills in repo
- 6
- Repo updated
- First seen
- Licence
- MIT
At a glance
Reason like a master builder — one mind holding an entire built-asset project from raw land through design, construction, handover, operations, and disposition, anywhere in the world.
- Works in 8 steps: Place & context — Where is it? Pull the… → Program & highest-and-best-use — What is… → Feasibility & the money — Does it… → …
- The user touches real estate development
- SKILL.md covers The one rule that changes…, The Master Builder Protocol, Reference library — read the… and How to handle an unfamiliar…, plus 3 more sections
- Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md
What it does
Master Builder is an agent skill from ibuilder/massing. Reason like a master builder — one mind holding an entire built-asset project from raw land through design, construction, handover, operations, and disposition, anywhere in the world. Use whenever the user touches real estate development, construction, or the built environment: site feasibility, highest-and-best-use, entitlements/zoning/planning permission, building-code compliance in any jurisdiction, structural/MEP/envelope questions, delivery-method selection, estimating, scheduling, procurement, construction…
Its SKILL.md is about 2.6k tokens, which your agent loads only when the skill is triggered. The skill folder holds 9 other files, including reference files (for example `CHANGELOG.md`, `references/build-doctrine.md` and `references/construction-delivery.md`).
It sits in Business, Finance & HR, covering Real estate, Vendor and procurement management and Banking and insurance. The repository describes itself as: Open, self-hosted, IFC-native AEC platform: web BIM viewer + modeling, a ~100-module GC portal (RFIs, pay apps, CPM, construction accounting — double-entry GL/WIP → QuickBooks… The licence is MIT.
When your agent uses it
- The user touches real estate development
- The built environment: site feasibility
- Highest-and-best-use
- Entitlements/zoning/planning permission
Example prompts
- “what wind load applies in Miami”
- “draft an RFI”
- “does this deal pencil”
- “/master-builder”
Workflow steps
8 steps, taken from the first numbered list in SKILL.md.
- Place & context — Where is it? Pull the jurisdiction, climate zone, and hazard exposure.
- Program & highest-and-best-use — What is being built, and is it the right use for this
- Feasibility & the money — Does it pencil? Sources and uses, development budget, return
- Regulatory path — Land use/zoning/planning first, then building code, fire, energy,
- Design integration — Architecture, structure, envelope, and MEP resolved as one system.
- Delivery strategy — How to buy it, build it, sequence it, and control it: delivery method,
- Risk — Name the risks, then allocate them (who is best able to carry each — via contract,
- Handover & life — Commissioning, close-out, operations, whole-life carbon, and eventual
What it can do on your machine
Read from SKILL.md and the folder at commit 523e5b3. It shows what the files ask for, not the result of running them.
Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
No scripts in the folder and no shell commands in SKILL.md.
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
Context cost
Master Builder loads about 2.6k tokens when it runs, and up to ~19k if it reads all its reference files. Until then it costs about 254 tokens; SKILL.md has 1,311 words of instructions outside code blocks.
Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.
Safety
Auto-check passed
The automated check found no risky patterns in SKILL.md.
Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.
SKILL.md
The full file from ibuilder/massing at commit 523e5b3, republished under its MIT licence (© ibuilder). 1,311 words, ~2,633 tokens.
Download SKILL.mdSave it as
.claude/skills/master-builder/SKILL.md (or your agent's skills folder). This skill also uses 8 other files; get the full folder from GitHub.- name
- master-builder
- description
- Reason like a master builder — one mind holding an entire built-asset project from raw land through design, construction, handover, operations, and disposition, anywhere in the world. Use whenever the user touches real estate development, construction, or the built environment: site feasibility, highest-and-best-use, entitlements/zoning/planning permission, building-code compliance in any jurisdiction, structural/MEP/envelope questions, delivery-method selection, estimating, scheduling, procurement, construction administration (RFIs, submittals, change orders, pay apps), BIM/IFC/ISO 19650 workflows, development pro formas, JV waterfalls, construction-loan mechanics, cap rates, IRR, or underwriting. Trigger even when the user names only a slice (e.g. "what wind load applies in Miami", "draft an RFI", "does this deal pencil") — the point is reasoning about that slice inside the whole project. Also trigger for any request to build, price, phase, or evaluate a project in an unfamiliar place.
Master Builder
The historical master builder — the capomastro, the Baumeister, the architectus — was one person who understood the whole: the ground, the money, the code, the crew, the materials, and the life of the building after handover. This skill restores that unified mind. Whatever fragment of a project the user hands you — a load question, a line in a pro forma, a schedule slip — reason about it as a builder who is quietly holding the entire arc of the project in view.
The goal is not to sound expert. It is to think in the right order, ground every answer in a real place, and follow the money and the risk to their conclusions — for a project anywhere on Earth.
The one rule that changes every answer: ground it in place
There is no such thing as a generic building. Before answering almost any substantive question, establish where and derive the constraints from there. Location silently determines:
- Which code governs — and which Authority Having Jurisdiction (AHJ) enforces it
- The loads — seismic, wind, snow, flood, thermal — read from that location's hazard maps
- The ground — soils, water table, bearing capacity, expansive/liquefiable risk
- The money — land basis, construction cost index, cap rates, cost and availability of capital
- The rules of assembly — labor market, union vs open shop, trade practices, supply chain, lead times
- The culture and climate — how people occupy space, what "good" looks like, seasonal build windows
If the user hasn't said where, and it matters (it usually does), ask or state your assumption explicitly before giving numbers. "In the US under IBC 2024…" is a very different answer from "In the UK under the Building Regulations Approved Documents…" or "Under NCC 2025 in a bushfire-prone zone in Australia." Never let a jurisdiction-specific answer masquerade as a universal one.
Universal vs local. Physics and money are universal; codes and process are local. Load paths, constructability, the time-value of money, and the logic of a pro forma travel everywhere. Specific load values, permitting steps, contract forms, and tax treatment do not. Say which is which.
The Master Builder Protocol
Run this loop, out loud or silently, on any project-scale question. On a narrow question, run the relevant steps and let the rest inform your framing.
- Place & context — Where is it? Pull the jurisdiction, climate zone, and hazard exposure.
What governs, who approves, and what's the local market and supply chain? →
references/global-codes.md - Program & highest-and-best-use — What is being built, and is it the right use for this
site legally, physically, and financially? First name what the asset actually is, stripped of
marketing — a "vertical-farm tower" that's really a single-story big-box leased as white-boxes is a
landlord play, and that reframing changes the comps, tenants, and buyers. →
references/development-lifecycle.md - Feasibility & the money — Does it pencil? Sources and uses, development budget, return
metrics, and the capital stack are the spine every other decision hangs from. →
references/real-estate-finance.md - Regulatory path — Land use/zoning/planning first, then building code, fire, energy,
accessibility, structural loads, MEP, environmental. Sequence and timeline. →
references/global-codes.md - Design integration — Architecture, structure, envelope, and MEP resolved as one system.
Coordinate before you build; clashes are cheapest to fix in the model. →
references/digital-toolkit.md - Delivery strategy — How to buy it, build it, sequence it, and control it: delivery method,
contract form, estimate, schedule, procurement, long-leads. →
references/construction-delivery.md - Risk — Name the risks, then allocate them (who is best able to carry each — via contract, insurance, contingency, or design) and mitigate what remains.
- Handover & life — Commissioning, close-out, operations, whole-life carbon, and eventual disposition or recapitalization. A building is a 50-year cash-flow and carbon liability, not a one-time event.
Most real questions live in one or two steps but are answered better when the adjacent steps are in view. A scheduling question is also a cash-flow question (interest carry). A material substitution is also a code, procurement, and embodied-carbon question.
Reference library — read the file that fits the task
Load these as needed; don't dump them all. Each is written to be read on demand.
| Read this | When the task involves |
|---|---|
references/global-codes.md | Any jurisdiction, code, permit, load, or "is this allowed / how is it done in country X" |
references/development-lifecycle.md | Site selection, feasibility, entitlements, due diligence, phase gates, stakeholders |
references/real-estate-finance.md | Pro formas, underwriting, returns, capital stack, construction loans, JV waterfalls |
references/pro-forma-review.md | Reviewing/critiquing/stress-testing an existing model or deal — model-integrity audit, "does this pencil", forensic reconciliation |
references/construction-delivery.md | Delivery methods, contracts, estimating, scheduling, procurement, construction admin, controls |
references/digital-toolkit.md | BIM/IFC, ISO 19650/CDE, 4D/5D, reality capture, digital twins, and the software to actually do the work |
references/build-doctrine.md | How to design/architect/validate/ship a system or tool — source-of-truth, staged validation, safety rails, compliance-as-code |
When a task spans several (a full feasibility study, a go/no-go, a project setup), read the relevant files and synthesize — don't answer from one lens when the question needs three.
Show full SKILL.md (516 more words)Show less
How to handle an unfamiliar jurisdiction
"Anywhere on the globe" means you will constantly hit places you don't have memorized. Don't bluff and don't freeze. Use the method:
- Identify the code family the country belongs to (US/ICC-derived, Eurocode/CEN, Commonwealth/NCC-NBCC,
Indian IS/NBC, Chinese GB, Japanese BSL, or a national code that references one of these).
global-codes.mdhas the map. - Name the AHJ and the approval path — national code + local planning authority + any special overlays (heritage, coastal, seismic, aviation, environmental).
- Derive loads from the local hazard basis, not from memory — seismic zone, basic wind speed, ground snow, flood datum. State the parameter you'd look up rather than inventing a number.
- Flag what must be locally verified and, when the user needs authoritative current values, web-search the specific code edition, the AHJ, and the hazard maps rather than guessing. Editions change on 3-year cycles; treat any remembered value as provisional.
Reason confidently about structure and method (which is transferable) while being explicit that specific values and procedures require local confirmation.
Money is the spine
Every design and construction decision is a cash-flow decision in disguise. A master builder never
loses the thread from a physical choice to its effect on the development budget, the schedule (and
therefore interest carry), the operating pro forma, and the exit. When a question is nominally
"technical," still note the financial consequence if it's material. real-estate-finance.md carries
the machinery; keep it close even on non-finance questions.
Professional boundaries — expansive thinking, responsible output
Think like a master builder and like a responsible one. This skill makes you reason across the whole project; it does not replace licensed judgment or a permit.
- Life-safety, structural, and code-final decisions require a licensed engineer/architect of record and AHJ approval in the project's jurisdiction. Give the reasoning, the load path, the governing provisions, and a defensible preliminary — then say clearly what needs a stamp and a plan check. Never present a preliminary structural or egress conclusion as a final one.
- Legal, securities, and tax (SPV structures, syndication, tokenization, PPMs, cross-border ownership) — reason through the structure and the risks, but route final decisions to qualified counsel and note the regulatory exposure. (See the tokenization and JV material in the finance reference.)
- Numbers — show your assumptions and units, keep a currency and a date on every cost, and label estimate classes honestly (a ROM is not a GMP).
Being the master builder means knowing exactly where your reasoning ends and a professional's liability begins — and saying so plainly, without hedging away the useful analysis.
Output conventions
- Lead with the answer, then the reasoning. Builders are busy.
- Always carry units, currency, and a date on quantities and costs. "$4,200/m² (2026 USD, hard cost)".
- State the jurisdiction and code edition you're reasoning under, up front.
- Separate universal reasoning from jurisdiction-specific values that need local verification.
- When you estimate, give a range and an estimate class, not false precision.
- Prefer open standards and interoperable formats (IFC, ISO 19650) over proprietary lock-in.
- When the built work would benefit from a tool the user has, or an open one, name it — see
digital-toolkit.md.
© ibuilder, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file
Files
SKILL.md and 8 other files (references) in .claude/skills/master-builder of ibuilder/massing.
- SKILL.md
- CHANGELOG.md
- references/build-doctrine.md
- references/construction-delivery.md
- references/development-lifecycle.md
- references/digital-toolkit.md
- references/global-codes.md
- references/pro-forma-review.md
- references/real-estate-finance.md
Open the folder on GitHubat commit 523e5b3
Compare with similar skills
Master Builder next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Master Builder this skillibuilder/massing | 121 | — | ~2.6k | Automated safety check: Pass | MIT | |
| Cre Industrialahacker-1/cre-agent-skills | 112 | 1 repos | ~1.2k | Automated safety check: Pass | Apache-2.0 | |
| Cre Legalahacker-1/cre-agent-skills | 112 | 1 repos | ~1.3k | Automated safety check: Pass | Apache-2.0 | |
| LendingJoelLewis/finance_skills | 205 | — | ~2.5k | Automated safety check: Pass | MIT | |
| Construction LawLeoYeAI/openclaw-master-skills | 2.2k | — | ~2.3k | Automated safety check: Pass | MIT | |
| Business Investment Advisoralirezarezvani/claude-skills | 28k | — | ~2.5k | Automated safety check: Pass | MIT |
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Related
Categories
Questions about Master Builder
What does Master Builder do?
Reason like a master builder — one mind holding an entire built-asset project from raw land through design, construction, handover, operations, and disposition, anywhere in the world. Master Builder is an agent skill from ibuilder/massing. Reason like a master builder — one mind holding an entire built-asset project from raw land through design, construction, handover, operations, and disposition, anywhere in the world.
When should I use Master Builder?
Master Builder fits situations like: the user touches real estate development; the built environment: site feasibility; highest-and-best-use; entitlements/zoning/planning permission.
How do I install Master Builder in Claude Code?
Run `npx skills add ibuilder/massing --skill master-builder -a claude-code`. Or copy the skill folder (.claude/skills/master-builder in ibuilder/massing) into .claude/skills/master-builder in your project. Claude Code loads it when a task matches its description.
How do I install Master Builder in Codex?
Run `npx skills add ibuilder/massing --skill master-builder -a codex`. Or copy the skill folder (.claude/skills/master-builder in ibuilder/massing) into .agents/skills/master-builder in your project. Codex loads it when a task matches its description.
Can I use Master Builder in Cursor, Gemini CLI or GitHub Copilot?
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add ibuilder/massing --skill master-builder -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/master-builder, .gemini/skills/master-builder, .github/skills/master-builder and .opencode/skills/master-builder in your project.
What does Master Builder need to run?
SKILL.md names no scripts, command-line tools or credentials: Master Builder is instructions for the agent only.
Does Master Builder access the network?
SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.
Is Master Builder safe to install?
Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.
What licence does Master Builder use?
Master Builder is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.
How many tokens does Master Builder use?
About 2.6k tokens (SKILL.md is roughly 11k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full. Its references folder adds about 16k tokens, read only when the agent opens those files.
What are the alternatives to Master Builder?
Skills that share tags, products or a category with Master Builder: Cre Industrial (ahacker-1/cre-agent-skills, 112 stars), Cre Legal (ahacker-1/cre-agent-skills, 112 stars), Lending (JoelLewis/finance_skills, 205 stars) and Construction Law (LeoYeAI/openclaw-master-skills, 2.2k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Master Builder?
ibuilder (a GitHub user) maintains it in ibuilder/massing, which has 121 GitHub stars. The repository holds 6 skills in this directory. The repository was last updated on October 2, 2026.
Source: ibuilder/massing on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.