Inventory

An environment is a copy of production, and no copy is complete. The database is masked. Some third party hosts are answered offline and some are refused outright. The traffic is whatever the manifest could point at. Every one of those is a deliberate choice, and each of them makes the copy differ from the thing it is a copy of in a way somebody reading a green check ought to know about.

af fidelity takes the inventory.

af fidelity
af fidelity -o json

Where the numbers come from

Every line comes from something the engine already knew and was not telling anybody.

Dimension	What it reads
services	The services the manifest declares, against the containers the runtime reports running.
database	Which golden the branch came from, whether that golden is verified, whether its signed attestation still matches its own signature, and how many tables and rows the branch holds.
third_party	The hosts the egress policy names, the mode each is in, and which mock pack answers for the ones in mock mode.
auth	Whether each declared persona actually has a row in the branch, and whether the way it signs in can be carried out here.
runtime	Where the environment runs.
traffic	Where the endpoint mix comes from, through the same code the load run uses.

Nothing is estimated and nothing is a constant somebody typed because the report needed a number.

The states

A component is in one of five states, worst to best.

State	Means
unmeasured	Its state could not be determined. Never counted as a pass or as a failure.
absent	The manifest asked for it and the environment does not have it.
refused	The policy deliberately does not reproduce it. A host in block mode is refused: the environment is doing what it was told, and it still does not reproduce that host.
substituted	Something stands in and behaves. A stateful mock pack, a captured message, a subset of the data.
reproduced	The real thing, present and answering.

A dimension’s verdict is the weakest measured state in it, because the one component that was not reproduced is what a reader needs, not the average of the ones that were.

Not measured is a result

An unmeasured component is excluded from the score and named with the reason. It is never quietly counted as either answer. This is the same discipline the insights report applies when it says what it could not read, and for the same reason: a report that silently omits a check reads exactly like a check that found nothing.

The cases that produce it today:

• The runtime could not be reached, or nothing is running for this environment. A stopped environment has not been shown to reproduce nothing.
• The database provider does not record which golden a branch came from.
• A host in synth mode. A model invents the response and the product already marks anything that touched it unverified rather than passed, so counting it as a reproduction would contradict the verdict.
• A mock rule that matches a pattern rather than one host, where which pack answers depends on the host the application reaches.
• A persona created through a provider’s own API rather than in the branch, which nothing here can read without calling it.

A dimension the manifest never asked for is excluded too, whole, with the reason. An environment that sends no traffic at all has not reproduced traffic perfectly.

The score

17 of 21 measured components are production's own, which is 81 percent.

Reproduced over measured. A substitution, a refusal and an absence are all in the denominator and none of them is in the numerator, which is what makes the number mean “how much of this is production” rather than “how much of this went to plan”. Nothing unmeasured is in either half, and every exclusion is printed under the table with the reason it was excluded.

When nothing could be measured there is no score. That is not nought percent and is never rendered as one.

The per dimension verdict is the part to read. A change to billing cares about the third party hosts and not about traffic; a migration cares about the data and about neither. One averaged number hides whichever of those is yours, which is why the score comes after the table and carries its own definition every time it is printed.

Third party reproduction is mostly low today, and says so

Only one mock pack ships, for Stripe. A host in mock mode with no pack answering it is absent, and the report says exactly that: every request to it is refused with a 404. A host in mock mode with a pack that keeps what was created is a better reproduction than one whose pack returns canned answers, and both are better than a host the policy blocks. The report distinguishes all three rather than averaging them into one word.

Requiring a dimension

fidelity:
  enabled: true
  require: [database, services]

af fidelity exits 6 with AF-FID-001 when a required dimension was measured and some component of it was not reproduced.

It exits 1 with AF-FID-002 when a required dimension could not be measured, which is neither met nor broken. The two are separate on purpose. A dimension measured and found wanting is a fact about the environment; a dimension nothing could measure is a fact about what we could see, and reporting the second as the first is how a check stops being believed.

runtime is reported and is not comparable today, because nothing in the manifest says what production runs on, so there is no other side to the comparison. Requiring it fails with AF-FID-002 saying so.

Turning the inventory off with enabled: false means it is not taken, which is not the same as everything having passed, and the command says so rather than printing an empty report. A manifest that disables the inventory and still names dimensions under require is refused: a requirement nothing evaluates reads in review as a gate that is enforced.