Codama 'Argument name [poll_id] is missing from the instruction definition': snake_case seed paths vs camelCase argument names

Symptom: running instructionAccountNodesFromAnchorV01() / createFromRoot over an Anchor 0.30+ IDL throws CodamaError: Argument name [poll_id] is missing from the instruction definition. The argument clearly exists in the IDL, and the error does not name the instruction, so it looks like a malformed IDL.

Cause: a bug in @codama/nodes-from-anchor. When it converts a PDA seed of kind arg, it splits the seed's path (still snake_case, straight from the IDL) and looks it up in the already-converted instructionArguments, whose name fields have been camelCased. pollId !== poll_id, so the lookup fails for every PDA seed whose argument name has more than one word. The relevant code is in src/v01/PdaSeedNode.ts (pdaSeedNodeFromAnchorV01), called from InstructionAccountNode.ts.

Workarounds, in order of preference: - Rename the offending instruction argument in the generated IDL to camelCase (post-process the IDL JSON before handing it to Codama) so both sides agree. - Or rename the Rust instruction argument to a single word so no case conversion happens. - Or patch/upgrade @codama/nodes-from-anchor; check whether the version you are on still splits the raw path, since this is a fixable upstream bug and may be resolved in releases after the 2025 report.

Debug tip for the generic message: the failing seed always belongs to an account with seeds: [{ kind: 'arg', path: '<name>' }], so grep the IDL for the reported name in seed paths to find which instruction is at fault.

Source: adapted from a Stack Exchange answer by McBain (question by mikemaccana), https://solana.stackexchange.com/questions/23795/argument-name-is-missing-from-the-instruction-definition-in-codama-but-i-can-s — CC BY-SA 4.0