Matt Van Horn
bfba99827e
* feat(erlang): inspect BEAM IFF chunks and tables Replay the Erlang BEAM inspection workflow, including table bounds, OTP 28+ atom layouts, the shared absolute-path policy, and empty-path CLI coverage, without carrying GitHub workflow edits. Co-authored-by: morluto <morluto@users.noreply.github.com> * fix(erlang): use publicInputStrictObject for BEAM tool input inspect_erlang_beam advertised a public input built with bare z.strictObject, so later shared input-policy changes would miss it. Result and internal objects stay on their own constructors. Co-authored-by: morluto <morluto@users.noreply.github.com> --------- Co-authored-by: Cursor Agent <cursoragent@cursor.com> Co-authored-by: morluto <morluto@users.noreply.github.com>
1.8 KiB
Erlang BEAM files
inspect_erlang_beam / inspect-erlang-beam answers whether one selected
local file is a FOR1/BEAM IFF container, which chunks that form stores, and
which atom, export, import, lambda, and Code-header fields those chunks carry.
It reads the file without executing bytecode and does not require an Erlang
installation or BEAM emulator.
rea inspect-erlang-beam /absolute/path/to/app.beam --json
The CLI resolves relative paths against the caller's working directory. MCP requires an absolute filesystem path and preserves that exact selection:
{
"name": "inspect_erlang_beam",
"arguments": { "path": "/artifacts/app.beam" }
}
Observations
The inline Evidence result contains the artifact path, SHA-256, and byte length.
chunks lists every IFF chunk name, file range, and payload SHA-256.
When AtU8 or Atom is present, atoms is the 1-based name table and
module is atom 1. Both the pre-OTP 28 table and the OTP 28+ compact table
(negated count, compact-encoded name lengths) are read. exports, imports, and lambdas resolve atom indices to
those names when the table is present; unresolved indices keep function or
module null.
code reports the Code chunk instruction-set, opcode maximum, label count,
function count, and the instruction stream's file range. Missing optional
tables are null, not empty-everywhere.
Limits and failures
The selected file is limited to 64 MiB by default (512 MiB maximum). At most
64 chunks and 4096 atoms are examined by default, and at most 65536 export,
import, and lambda rows together. Malformed FOR1/BEAM headers, truncated
chunks, and AtU8 names that are not valid UTF-8 fail without partial success.
This workflow does not execute bytecode, inflate LitT literals, or decode
Attr/CInf external-term payloads.