Receipts

Understand what receipts prove, what they contain, and how to validate them.

Receipts

A receipt is a cryptographic thumbprint of a completed REE execution. It chains together hashes of the inputs (model, prompt, configuration) and outputs (generated tokens) so that anyone can verify whether a claimed result is consistent with the claimed inputs without needing to re-execute the computation.

After every successful run, the TUI displays the path to the receipt file. Receipts are designed to be shared with others, who can then use them to verify that they can reproduce the same output using REE.

We recommend sharing receipts alongside any claims about model behavior, so that others can verify those claims for themselves.

What You’re Actually Verifying

REE guarantees reproducibility of computation, not the correctness of inputs or the correctness of the outputs.

A receipt proves that a given model produced a given output from a given prompt. It does not verify that the information in the prompt is accurate or that any action was taken based on the output.

What a Receipt Contains

Field	Type	Description
model_name	string	Hugging Face model ID used for inference.
commit_hash	string	Specific Hugging Face model revision (git commit hash).
config_hash	string	Hash of the full task configuration (config.json).
prompt	string	The raw prompt text that was provided.
prompt_hash	string	Hash of the prompt.
parameters	object	Sampling and generation parameters used (temperature, top_k, top_p, etc.).
parameters_hash	string	Hash of the parameters object.
tokens_hash	string	Hash of the generated output tokens.
token_count	int	Number of tokens generated.
finish_reason	string	Why generation stopped: "eos_token" (model produced end-of-sequence naturally) or "max_length" (hit the max token limit).
text_output	string	The decoded text output of the generation.
device_type	string	Device used for inference (e.g., cpu, cuda).
device_name	string	Specific device identifier.
receipt_hash	string	Hash over commit_hash, config_hash, prompt_hash, parameters_hash, and tokens_hash.
version	string	The receipt schema version.
ree_version	string	The version of the REE SDK that generated the receipt.

What a Receipt Does NOT Contain

A receipt does not include the model weights themselves, intermediate compilation artifacts, or timing/performance data.

It is a proof of what was computed and what was produced, not how fast or on which exact machine, though the receipt does include both device_type and device_name (for example, "NVIDIA A100") as informational metadata. Neither of these are part of the receipt_hash.

Validating a Receipt

Validation recomputes hashes from the data stored within the receipt itself and compares them against the hash values in the receipt. This checks internal consistency, that the receipt hasn't been tampered with or corrupted, not that it matches anything on disk.

A valid receipt must satisfy all of the following:

• prompt_hash matches a recomputed hash of the prompt

• parameters_hash matches a recomputed hash of the parameters

• receipt_hash matches a recomputed hash over all receipt fields

To validate a receipt. i.e., to check that all its hashes are internally consistent, switch the Subcommand field to validate and provide the path to a receipt JSON file saved locally on your device.

This would be either:

• A receipt you generated yourself

• or, a JSON file you create with the contents of someone else's receipt (e.g., by copying the JSON from someone else's receipt and saving it as a local file)

Verifying a Receipt

Validation checks that a receipt is well-formed, but it doesn't prove the result is reproducible. To do that, use verify.

Switch the Subcommand to verify and paste the receipt path into the Receipt Path field, then press r to run.

REE will re-execute the full inference pipeline described in the receipt using the same model, prompt and parameters and compare the output against what the receipt claims. If the outputs match, the receipt is verified.

This is the check you'd use when someone sends you a receipt and you want to independently confirm the result on your own hardware.