Invoice logo

Invoice

Organization
AlpacaLabsLLC
invoice

Maintain an append-only project INVOICES.csv ledger from explicit billing facts and recorded lifecycle evidence; never infer charges or payment from activity or time logs.

Overview

PublisherAlpacaLabsLLC
Repositoryskills-for-architects
Skill nameinvoice
Stars
386
Forks
81
Bundled files
2
LicenseMIT
Links
  • Markdown instructions

    A SKILL.md file the model loads on demand, so it only costs tokens when a request actually matches.

  • Works with any LLM

    AI skills are plain Markdown, not provider-specific code, so this works with GPT, Claude, Gemini, Grok, or a local model.

  • 2 bundled files

    Scripts, templates, and references the model can read while it works. Files are read-only and never executed.

  • Open source

    Published by AlpacaLabsLLC on GitHub. Read the source before you install it.

Installation

Install the Invoice AI skill in TypingMind to use it with any LLM, or drop it into another agent that reads SKILL.md.

1

Install in TypingMind

TypingMind installs a skill straight from its GitHub folder — it reads SKILL.md, bundles the resource files, and stores the result locally.

  1. Open the app and go to Plugins → Skills.
  2. Choose "Install from GitHub".
  3. Paste the skill folder URL below and confirm.
    https://github.com/AlpacaLabsLLC/skills-for-architects/tree/main/skills/invoice
  4. Enable the skill in any chat where you want it available.
Plugins → Skills → Add skill → From GitHub URL, then paste the folder URL and press Continue.
2

Install in another agent

Any agent that reads the Agent Skills format can use this skill — copy the folder into that agent's skills directory.

Claude Code — .claude/skills
git clone --depth 1 https://github.com/AlpacaLabsLLC/skills-for-architects.git /tmp/skills-for-architects
mkdir -p .claude/skills
cp -r /tmp/skills-for-architects/skills/invoice .claude/skills/invoice
Restart Claude Code after copying so it picks up the new skill.

Use it in TypingMind

Enable Invoice in any TypingMind chat and the model takes it from there. Its name and description sit in the system prompt, and the moment a request matches, the model loads the full instructions itself — you never invoke it by hand, and it costs no tokens until it is actually used.

The model loads Invoice on its own as soon as a request matches it.

Works with any AI model

AI skills are plain Markdown instructions rather than provider-specific code, so Invoice is not tied to the model it was written for. Install it once in TypingMind and use it with GPT-5, Claude, Gemini, Grok, DeepSeek, Mistral, Llama, or a local model you run yourself — all on your own API keys.

  • Loaded only when it is needed

    The system prompt carries just the name and description. The instructions are fetched on the first matching request, so an idle skill costs nothing.

  • Switch models mid-chat

    Because the skill is instructions rather than code, changing model does not break it — the next model reads the same SKILL.md.

Skill instructions

This is the SKILL.md content the model loads. Read it before installing — a skill is instructions your model will follow.

/as:invoice

Before acting, read the host contract, this component's declaration (skill:invoice), and applicable workspace semantics. Load only the required modes from the shared catalog.

Use the host adapter and native context procedure. The harness performs the semantic operations below using its available native tools; ordinary task-specific code is allowed. No Arch Studio runtime, installer, bridge, supplied script or source checkout is required. Direct skill invocation is valid. Existing exact authorization persists; ask only for material missing facts or unavailable access.

Own INVOICES.csv; invoice documents are registered through receive with kind invoice. No agreement is required: amounts and currency may come from confirmed terms in PROJECT.md's Agreement section or explicit user input. Never infer billability, payment, hours or completion from task/time/activity signals.

Before changing records

Before persistent changes, follow the native mutation sequence: Inspect → Prepare → Verify preparation → Apply → Verify result → Complete. Inspect pending work first. Finish and verify preparation before the first canonical write: separately reread every saved original and prepared file, check its complete actual bytes, establish durable saving, and inspect actual permissions, ownership and ACLs. Merely writing recovery files does not finish verification. Apply only that verified set. Mark complete only after fresh readback validates the entire affected result and its relationships. Read-only requests and inline drafts need no publication sequence.

Ledger append/lifecycle changes affect the complete INVOICES.csv only; guard any cited invoice document or Agreement evidence without editing it. Invoice-document creation/registration is a separate authorized document-plus-DOCUMENTS.csv operation. A next-ID preview is read-only and does not reserve identity.

Use invoice.status to list preserved rows and separate totals by currency. invoice.allocate reports the next permanent I-number without reserving it; append allocates against the actual current register. invoice.init reports the fresh setup register without replacing it.

For invoice.append, preview invoice number, billing period, currency, base, expenses, total, explicit sent/paid dates/status, correction target and optional registered invoice document ID. Decimal arithmetic must reconcile base + expenses = total. Preserve malformed registers; do not guess missing amounts or silently reuse an invoice number. Corrections append distinct rows referencing the original; do not erase its history or silently net correction totals.

invoice.set-lifecycle records sent/paid/void date evidence without deleting a row. Actual sending or bank reconciliation requires its own available capability and authorization. A lifecycle update never manufactures payment. Re-read the row and report its ID, facts and any unmet external action.

Native execution and completion

Follow the exact INVOICES semantics for whole-register validation, decimal values, permanent IDs, number uniqueness, correction references, registered documents, lifecycle history and retry identity. These are native semantic operations, not a script interface. invoice.init, invoice.allocate and invoice.status are read-only; init never creates or replaces a missing register. A displayed next ID is not reserved.

Confirm missing commercial facts before append; preserve existing authorization for exact rows. Use decimal arithmetic for all checks and totals, without binary floating-point rounding. Status totals include all nonvoid rows per currency; they are not a calculation of outstanding balance. Corrections retain their own signed, explicit amounts and distinct invoice number; no netting or payment inference is authorized by the presence of an earlier row.

Before any append or lifecycle change, bind exact intent and actual current register; reconcile concurrent changes or refuse before publication. Use the verified single-register preparation from the mutation sequence. After interruption, inspect actual old/new state and history before retry; do not duplicate an invoice or lifecycle event.

Re-read the canonical destination and report register path, invoice ID/number, exact amounts and currency, explicit status/dates, appended event count and any unmet external action. Recording sent or paid evidence does not send a message, invoice the customer or perform bank reconciliation.

Bundled files

The model reads these on demand while the skill is loaded. They are exposed as readable files and are never executed.

Frequently asked questions

What does the Invoice AI skill do?

Maintain an append-only project INVOICES.csv ledger from explicit billing facts and recorded lifecycle evidence; never infer charges or payment from activity or time logs.

Why use Invoice on TypingMind?

Because you install it once and use it with any model. Invoice is plain Markdown rather than provider-specific code, so the same skill runs on GPT-5, Claude, Gemini, Grok, or a local model — and you can switch model mid-chat without it breaking. TypingMind runs on your own API keys, so you pay providers directly instead of a per-seat subscription, and your skills and chats stay in your own storage.

How do I install Invoice in TypingMind?

Open Plugins → Skills → Install from GitHub in TypingMind and paste https://github.com/AlpacaLabsLLC/skills-for-architects/tree/main/skills/invoice. TypingMind reads its SKILL.md and bundles its files and installs it as a skill you can enable per chat.

Which AI models can use Invoice?

Any model you connect in TypingMind. AI skills are plain Markdown instructions rather than provider-specific code, so GPT, Claude, Gemini, Grok, and local models can all load this skill when a request matches it.

How many AI models can I use with Invoice?

As many as you like. As long as a model supports skills, you can use Invoice with it — GPT, Claude, Gemini, Grok, DeepSeek, Mistral, Llama and more — all on TypingMind with your own API keys.

Is the Invoice AI skill free?

Yes. It is published on GitHub by AlpacaLabsLLC under the MIT license. You only pay your own AI provider for the tokens you use.

What are AI skills?

An AI skill is a reusable instruction bundle that teaches an AI model how to do one specific task. It follows the open Agent Skills format: a SKILL.md file with a name and description, plus any scripts, templates or reference files the model may need. The model reads the instructions only when your request matches the skill, so an installed skill costs nothing until it is used.

How are AI skills different from plugins or MCP servers?

A plugin or MCP server gives a model new tools to call — code that runs somewhere and returns a result. An AI skill gives the model knowledge and process instead: how to approach a task, which steps to follow, what good output looks like. Skills are plain Markdown, so they need no server, no API key and no runtime, and they work with any model.

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