# zero-amount-unshielded-send

> Review canonical unshielded send amounts with a zero-inclusive successful-history range.

Canonical: https://nightshade.dicksonwu.xyz/rules/zero-amount-unshielded-send.html
Release: Nightshade 0.1.1 (v0.1.1)

| Field | Value |
| --- | --- |
| Rule ID | `zero-amount-unshielded-send` |
| Severity | info |
| Confidence | varies |
| Maturity | experimental |
| Selection | Opt-in |
| Policy intent | not required |
| Default enabled | no |
| Category | Other active opt-ins / Token, coin and value transfers |
| Engine facts used | canonical-invocation-snapshots, all-predicates, exact-numeric-operands, completed-entries |
| Release | v0.1.1 |

## Selection and scope

Not selected by default. Select it with `--detectors` or the `detectors` list in nightshade.json. Either one replaces profile selection, so list every rule you want.

```sh
./.nightshade/node_modules/.bin/nightshade ./contracts --detectors zero-amount-unshielded-send
./.nightshade/node_modules/.bin/nightshade detector show zero-amount-unshielded-send
```

The first command runs only this rule; `--detectors` takes a comma-separated list. The second prints the rule's metadata from your installed version.

Severity is review priority. It does not express exploitability or impact. Confidence is detector metadata, not a probability. All built-in rules are experimental.

Compiler scope: the engine supports the pinned profiles 0.28.0, 0.29.0, 0.30.0, 0.31.1, 0.33.0-rc.2, 0.34.0, 0.35.0-rc.1 and 0.35.0, with ZKIR2 by default. Support for this rule can be narrower; the rule documentation below states any narrower scope.

## Corpus checks

Synthetic corpus checks for this rule in the 0.1.1 proof run. A check counts only with compiler acceptance and complete analysis.

| Positive detected | Corrected quiet | Lookalike quiet | Other negative quiet | Incomplete |
| ---: | ---: | ---: | ---: | ---: |
| 1/1 | 1/1 | 1/1 | 0/0 | 0 |

No deviations were recorded for this rule.

These are behavior checks on synthetic fixtures, not a precision or recall estimate. See [evaluation](https://nightshade.dicksonwu.xyz/evaluation.md#synthetic-corpus).

## Rule documentation

From https://github.com/DicksonWu654/nightshade/blob/v0.1.1/docs/detectors/zero-amount-unshielded-send.md at v0.1.1.

Availability: **opt-in**; severity **info**. This rule reviews canonical
`CompactStandardLibrary.sendUnshielded` calls whose amount retains zero in its
modeled successful-history range. The amount is the second argument (index 1).

```compact
sendUnshielded(disclose(color), disclose(amount), disclose(recipient));
```

An unsigned amount permits zero until an effective constraint excludes it.
A literal zero is also a review candidate. Require `amount > 0` before sending
when the intended operation requires a positive amount, or handle zero explicitly
without invoking the send. A local circuit sharing the spelling is not the
canonical operation.

Zero-valued transfers can be intentional for protocol bookkeeping or a supported
no-op. This informational rule reports only the modeled source amount; it does
not infer application policy, prove a transaction can execute, or establish
economic impact. Unsupported histories and exhausted budgets remain incomplete.

## Suppress a match

If a match is intentional, suppress it on the line before with the exact rule ID and a reason of at least eight characters:

```compact
// nightshade-disable-next-line zero-amount-unshielded-send -- Reason this match is intentional
```

Diagnostics cannot be suppressed, and an unmatched directive for a selected rule makes analysis incomplete. See [configuration](https://nightshade.dicksonwu.xyz/configuration.md#suppress-an-intentional-match) for fingerprint suppressions and baselines.

## References

- [Rule source document at v0.1.1](https://github.com/DicksonWu654/nightshade/blob/v0.1.1/docs/detectors/zero-amount-unshielded-send.md)
- [Catalog entry in rules.json](https://nightshade.dicksonwu.xyz/rules.json)
- [All rules](https://nightshade.dicksonwu.xyz/rules.md#token-coin-and-value-transfers)
- [Limitations](https://nightshade.dicksonwu.xyz/limitations.md)