[raymondk]

Three things a user saw raw before, from #824 (commit 18f7794, gateway part), code by Josh:

• a --gateway that cannot be a canister (anonymous principal, management canister, an identity's principal) is refused before any network is asked (NotACanister);
• a canister that serves no get_card_terms is said to be no gateway (NotAGateway), where the user saw the replica's raw IC0536 "has no query method";
• a boundary node's HTTP 4xx canister_not_found reads as the gateway being absent, as a replica's IC0301 does.

Names is how the command's prose names the gateway: CyclePay, and Stripe's page, only for CyclePay's own gateway; "the gateway" and "the gateway's payment page" for any other. Later PRs in the stack reuse it.

Not included from the source commit: the -n local-outside-a-project message, the MAINNET_HINT rewording and the 80-column message wrapping.

Tests: three unit tests in cyclepay/tests.rs, another_gateway_is_not_called_cyclepay, and the pocket-ic integration tests cycles_buy_refuses_a_gateway_that_cannot_be_one and cycles_buy_names_a_canister_that_is_no_gateway.

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Part of restacking #824 into small PRs, one fix each, stacked on main in this order: cycles-buy/01-json-implies-yes → 02-arg-group → 03-gateway → 04-qr-colours → 05-paste-flags → then the wait, its follow-up text and the --json fields. Each PR targets the one below it; after the one below merges, retarget to main.

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https://claude.ai/code/session_01Twxau844tMTwyHpQJEbmBo

[Copilot]

🟢 Approval recommended

The focused changes and regression coverage reveal no blocking issues; tests were inspected but not executed.

No open issues 🎉

What changed in this PR

Improves icp cycles buy gateway diagnostics and avoids naming CyclePay or Stripe when using another gateway.

Changes:

• Rejects invalid gateway principals before network access.
• Clarifies missing-canister and missing-gateway-method errors.
• Updates gateway-specific wording, regression tests, and documentation.

File	Description
docs/​guides/​tokens-and-cycles.md	Updates the confirmation example.
crates/​icp-cli/​tests/​cycles_tests.rs	Tests gateway errors and generic delivery wording.
crates/​icp-cli/​src/​cyclepay/​tests.rs	Tests principal validation and error mapping.
crates/​icp-cli/​src/​cyclepay/​purchase.rs	Validates gateway IDs and translates network errors.
crates/​icp-cli/​src/​commands/​cycles/​buy.rs	Applies validation and gateway-specific names.
CHANGELOG.md	Records diagnostic and wording improvements.

_{Review effort: Balanced}