A finished file shows the result of work. On its own, it tells little about the documented writing session. ExtraProof captures information about that session in a Creation Record.
This is a digitally signed dataset that writers can share with their text. It contains recorded session data and can be linked to a particular file version. Recipients can then verify the record themselves.
For a classroom submission, this is an additional information source: teachers see what session information is available and whether the submitted file matches the stored file binding. The path from recording to verification explains what this means.
Recording starts with a deliberate decision
In ExtraProof Writer, select your writing app and start a session. Sensor status shows which signals can be captured. You can pause and resume recording. Interruptions and technical recording limitations form part of the documentation.
The Creation Record brings together:
- Session context
- Session identifier, selected application, recorder version and recording mode.
- Event sequence
- Captured events in order, with their associated times.
- Completion
- Session status and, if a file was selected, its fingerprint and size in bytes.
- Verification data
- The digital signature and event-chain links used to check the record’s integrity.
Available observations depend on the integration and technical prerequisites. The session therefore describes only what was actually captured. Local times come from the device; they are not independently confirmed timestamps.
The fingerprint belongs to one exact file
Suppose you write project documentation and export it as a PDF. At the end of the session, you select that file. ExtraProof calculates its SHA-256 digital fingerprint and stores it in the record together with the byte count.
During later verification, the submitted file’s fingerprint is calculated again and compared. This establishes whether the exact bound version is present. An identical filename alone would not be enough.
Changing a paragraph afterwards or exporting the document again may produce different bytes. That version then no longer matches the existing binding. This is initially a finding about the file: the new version needs a new association.
Binding remains optional. Without it, the record’s integrity can be checked, but a submitted file cannot be compared against it. A matching binding alone also does not prove that the documented session produced the file.
The recipient can repeat verification
Writer can embed the record in a readable PDF evidence document or export it separately as JSON. In ExtraProof Verify the recipient selects this evidence. For file comparison, they also select the bound document version.
Verify checks the format, digital signature and event chain. The signature protects signed data; the chain links recorded events in sequence. Failures in these checks are shown as distinct findings. Comparison with the document file is displayed separately.
For a PDF, Verify extracts the embedded Creation Record. Visible PDF pages and the PDF signature are not part of this browser check. The result concerns the contained record and, if selected, the additional document file.
The identity behind the signing key is a separate question too. A mathematically valid key does not establish who owns it. If its fingerprint is known from an independent trusted source, Verify can compare it as an additional check.
A concrete starting point for follow-up questions
In teaching, the record can help discuss a submission more closely. Does the submitted version match? Is the documented session complete? Was there an observation gap that warrants explanation? Such questions relate to visible findings.
We do not calculate an AI percentage from this. A valid signature confirms the integrity of signed data. It does not automatically confirm the writer’s identity or the accuracy of every recorded observation. The origin of ideas, human authorship and the absence of AI cannot be proved from it alone either.
Fair assessment therefore needs rules agreed in advance: which tools are allowed, which part of the work should be documented, and how technical interruptions are handled. A record can support the subsequent conversation with concrete information. Responsible teachers still perform the subject assessment.
Review metadata before sharing
Writer stores sessions locally on your device. Activity telemetry contains no recorded characters or clipboard contents. Metadata such as the app identifier, session times and possibly the filename can still reveal information about your work. Before sharing, check what the record contains and who needs it.
No account is required to use Verify. Selected files are processed directly in the browser and are not uploaded for verification. File comparison does require the recipient to have the matching document version.
Technical basis of this article: documentation on Creation Records, signatures and trust and local processing. Information as of 7 October 2026.