Ask your AI assistant if Otis is right for you.

Paste this into your AI assistant

I’m thinking about using Otis (https://otisbase.com) for my client billing. Read https://otisbase.com/llms.txt and https://otisbase.com/how-it-works to learn what it does and what it doesn’t. If you can connect to MCP servers, try the read-only sample it describes. Then ask me a few short questions: what I bill for, how many clients I have, how I invoice today, and which AI assistant I use. Based on my answers, tell me honestly whether Otis would help me, what it would take over, and what it can’t do. If it’s a good fit, walk me through connecting it.
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Skills for every billing task. 11 skills in the Otis plugin: the menu, and one for each part of client billing.

Claude

  1. Download the plugin, otis-claude-0.1.0.zip, from the latest release.

  2. In Claude or Cowork, open Customize.

  3. Go to Plugins, choose Add, then Upload plugin, and choose the file.

  4. When Claude asks, connect Otis and sign in with the code we email you.

  5. Type /otis:menu to pick a skill.

ChatGPT

  1. In ChatGPT, open the Plugins page.

  2. Choose the + button, then Add custom MCP server.

  3. Name it Otisbase.

  4. Paste the server URL:

    https://mcp.otisbase.com/mcp

  5. For authentication, choose OAuth. If ChatGPT asks for a registration method, choose dynamic client registration.

  6. Create it, then sign in with the code we email you in the window that opens.

  7. Install the plugin ChatGPT creates.

  8. In a chat, type @, pick Otisbase and ask for the Otis menu.

Claude Code

  1. In your terminal, run:

    claude plugin install otis --marketplace otisbase/otis-plugins

  2. Start Claude Code and run /mcp.

  3. Choose otis and sign in with the code we email you.

  4. Type /otis:menu to pick a skill.

Codex

  1. Add the Otis marketplace:

    codex plugin marketplace add otisbase/otis-plugins

  2. Install the plugin:

    codex plugin add otis@otis

  3. Start a new Codex session.

  4. Sign in to Otis when it asks, with the code we email you.

  5. Type $otis:menu to pick a skill.

otisbase/otis-pluginsThe public Otis plugin marketplace, MIT licensed.

Menu

/otis:menuin Claude$otis:menuin Codex

Open the list of skills, then pick one by number or name.

Open the menu

Lists the ten skills by number. Opening it reads no records.

otis_menu

Pick a skill

Reply with a number or a name, or just describe the task.

no tools

Create invoice

/otis:create-invoicein Claude$otis:create-invoicein Codex

From ready work to an issued invoice, with your approval.

Find what’s ready

Reads the client and the work left to bill.

clients_list, billables_list

Add missing work

Records work you mention that isn’t saved yet.

billable_record

Draft

Builds a draft and reserves its work, so it can’t be billed twice.

invoice_draft

Check

Lists anything missing, such as the tax treatment.

invoice_check

Issue

Only after you approve the exact total.

invoice_issue

Cancel a draft

Releases its work for another invoice.

invoice_cancel_draft

Record work

/otis:record-workin Claude$otis:record-workin Codex

Time, services and AI usage, saved to the client.

Record time or a service

Hours or a fixed amount, saved to the client.

clients_list, billable_record

Record AI usage

Marked as measured or estimated. You supply the amount.

billable_record

Correct an entry

Before it is billed. The change stays in the history.

billables_list, billable_record

Add expense

/otis:add-expensein Claude$otis:add-expensein Codex

Costs you keep, and costs you bill back.

Record an expense

Vendor, category, date and cost.

expense_record

Bill it back

Adds one linked charge to the client, billed once.

expense_record

Correct an expense

Its linked charge updates with it.

expenses_list, expense_record

Clients

/otis:clientsin Claude$otis:clientsin Codex

Find, add and update the clients you bill.

Find a client

Searches your saved clients first, so nothing is duplicated.

clients_list

Add a client

Billing details, country, and business or consumer status.

client_save

Update details

Invoices already issued keep the details they went out with.

client_save

Invoices

/otis:invoicesin Claude$otis:invoicesin Codex

Review drafts, issued invoices and balances.

Review invoices

Drafts, issued invoices and their balances.

invoices_list, invoice_get

Check a draft

Shows what still blocks issuing it.

invoice_check

Cancel a draft

Only one you name, with a reason.

invoice_cancel_draft

Payments

/otis:paymentsin Claude$otis:paymentsin Codex

Review payments, or record one you received.

Review payments

What each invoice has received and still owes.

invoices_list, payments_list

Record a payment

Against an issued invoice, with a unique reference.

invoice_get, payment_record

Team

/otis:teamin Claude$otis:teamin Codex

Invitations and who can see or change records.

Accept an invitation

Joins a business you were invited to.

businesses_list, team_accept

See who has access

Owners, editors and viewers.

team_list

Invite or change a role

Owners only. You confirm the person and the role.

team_invite, team_member_set

Business settings

/otis:business-settingsin Claude$otis:business-settingsin Codex

Your business identity and invoice numbering.

Review your profile

Name, currency, billing address and invoice numbering.

business_get

Set up or update

Owners only. Currency locks once you have records.

business_set

Tax settings

/otis:tax-settingsin Claude$otis:tax-settingsin Codex

Tax guidance and the registrations you confirm.

Read the tax guide

Dated guidance for the US, Canada, the UK and Australia.

tax_guide

Save your tax profile

Registrations you confirm. Owners only.

business_get, tax_profile_set

Export

/otis:exportin Claude$otis:exportin Codex

Every record and its history, for your accountant.

Export records

Any record kind, or the audit history, page by page.

records_export

One URL for every MCP client. Add the server, sign in with your email, then ask Otis to set up your business. No password, no API key.

Server URLhttps://mcp.otisbase.com/mcp
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