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Arcus

Contact

One mailbox, read by a person.

No form, no chat widget, no calendar link, no switchboard. Everything arrives at [email protected], and the table below gives the subject line that routes each kind of message to the right treatment.

Write to [email protected]. Replies go out within five working days.

Routing

1Subject lines and response times

The times below are commitments rather than aspirations. If one is going to be missed, you will be told before it is missed.

What to write in the subject line
Subject lineUse it forResponse
Put a document set to the testThe corpus you run retrieval over and the questions you run against it. Back comes a straight read on which of the eleven measures would tell you something you do not already know, and what the labelling costs before it does5 working days
QuestionAnything about the measures, the boundary, or whether this applies to your pipeline5 working days
WrongTelling us the premise, the maths or a claim on this site is mistaken. The most welcome message on the list5 working days
Inspect the recordA copy of everything held about you, under clause 19 of the privacy policy30 days at the outside
Correct the recordFixing something wrong about you, or attaching your own statement to it, under clause 2030 days at the outside
Destroy the recordRemoving the correspondence and anything else held about you, under clause 2130 days at the outside
Privacy complaintAn objection to how information about you was handled, under clause 27Logged on arrival; the written outcome follows within 30 days
SecurityA suspected vulnerability in this website, or a suspected breachSame or next working day
PressMedia enquiries. The overview page sets out the measures and the boundary, and answers most of them5 working days
No form, on purpose

Any form that genuinely delivers needs a script behind it, an endpoint belonging to somebody else, and a store for the messages to pile up in. A mailbox needs none of the three. It also survives having JavaScript switched off, it leaves the sent copy sitting in your own outbox, and it means the thread belongs to both of us rather than only to whoever runs the database.

Detail

2What makes a message easy to answer

None of this is required. It shortens the exchange from three messages to one.

If you run a retrieval system

  • Roughly how many documents are in the index, and roughly how many questions a day it serves.
  • Whether you have any relevance judgements at all today, even an informal spreadsheet.
  • What made you look. Usually there is a specific answer that went wrong and somebody remembers it.

If you are reporting a defect on this website

  • The page, your browser and roughly what you were doing.
  • Whether JavaScript is switched off in your browser. These pages are built to work without it, so a fault that shows up only in that state is worth knowing about.

If you are reporting a security issue

  • Tell us before you tell the internet. A report made in good faith gets a grateful answer here, never a legal one.
  • This site is static. There is no login, no database and no user content, so the plausible surface is small, but the address is monitored for it regardless.

Limits

3What we cannot help with

Stated so that a message that will disappoint you is not sent in the first place.

  • Running or hosting your retrieval pipeline for you. Arcus grades a pipeline it does not serve, and an evaluator that serves the traffic it grades is marking its own homework.
  • Recommending a vector database or an embedding model. We have opinions and no evidence, and a recommendation without evidence is exactly what this whole site argues against. Measure the two against your own questions and the answer stops being a matter of taste.
  • Grading the answer a model wrote. Where the passages were right and the text was still wrong, Arcus says so and hands the question to the tools built for that half.
  • Investment enquiries. The company is not raising.

A short honest no arrives faster than a polite maybe, so that is what you will get.

Entity

4Who you are writing to

The registered details, and where to verify each of them without asking us.

Mail to that address reaches ARCUS AI PTY LTD, a proprietary company incorporated in Australia and based in New South Wales, trading as Arcus. Its ACN is 697 547 505, its ABN is 82 697 547 505, and it is registered for GST.

Neither number has to be taken on our word. The lookup at abr.business.gov.au returns the entity status and the GST position at no charge, and the company register at asic.gov.au holds the ACN record. Every one of those facts is set out line by line in the register block on the method page.

Documents requiring formal service go to the registered office ASIC holds against that ACN, which is the only address with that effect. Putting a different postal address on a contact page achieves nothing legally, so none appears here.

What happens to a message after it arrives is governed by the privacy policy: what is kept, for how long, and how to have it inspected, corrected or destroyed. Where a complaint to us settles nothing, clause 27 of that policy gives the external route to the Information Commissioner in full, with the postal address and the telephone number.