attune/work-summary/2026-02-remove-params-end-delimiter.md

Remove ---ATTUNE_PARAMS_END--- Delimiter Antipattern

Date: 2026-02-10

Summary

Removed all instances of the ---ATTUNE_PARAMS_END--- stdin delimiter from the entire project — source code, shell scripts, and documentation. This was an antipattern from the old two-phase stdin protocol where parameters and secrets were delivered as separate documents separated by this delimiter. The current protocol merges secrets into parameters as a single JSON document delivered via one readline(), making the delimiter unnecessary.

Background

The original stdin protocol wrote parameters and secrets in two phases:

1. Parameters JSON + \n---ATTUNE_PARAMS_END---\n
2. Secrets JSON + \n

This was already fixed in process_executor.rs and shell.rs (which write a single merged document followed by \n), but native.rs still had the old protocol, and all shell scripts and documentation still referenced it.

Changes Made

Source Code (1 file)

crates/worker/src/runtime/native.rs:

• Removed the ---ATTUNE_PARAMS_END--- delimiter write from execute_binary()
• Removed the separate secrets-writing block (matching the fix already applied to shell.rs and process_executor.rs)
• Added secrets-into-parameters merge in execute() before prepare_parameters() is called
• Now passes &std::collections::HashMap::new() for secrets to execute_binary()
• Stdin protocol is now: {merged_params}\n then close — consistent across all runtimes

Shell Scripts (9 files)

Updated all pack action scripts to read stdin until EOF instead of looking for the delimiter:

• packs/core/actions/echo.sh
• packs/core/actions/sleep.sh
• packs/core/actions/noop.sh
• packs/core/actions/http_request.sh
• packs/core/actions/build_pack_envs.sh
• packs/core/actions/download_packs.sh
• packs/core/actions/get_pack_dependencies.sh
• packs/core/actions/register_packs.sh
• packs/examples/actions/list_example.sh

In each script, removed the *"---ATTUNE_PARAMS_END---"*) break ;; case pattern. The while IFS= read -r line loop now terminates naturally at EOF when stdin is closed.

Documentation (9 files)

• docs/QUICKREF-dotenv-shell-actions.md — Updated template, format spec, and parsing examples
• docs/action-development-guide.md — Updated stdin protocol description, all Python/Node.js/Shell examples, troubleshooting section
• docs/actions/QUICKREF-parameter-delivery.md — Updated copy-paste templates and design change section
• docs/actions/README.md — Updated quick start Python example
• docs/actions/parameter-delivery.md — Updated protocol description, stdin content example, all code examples
• docs/packs/pack-structure.md — Updated Python stdin example
• docs/parameters/dotenv-parameter-format.md — Updated parsing examples, secret handling docs, troubleshooting

Work Summaries (5 files)

• work-summary/2025-02-05-FINAL-secure-parameters.md
• work-summary/2025-02-05-secure-parameter-delivery.md
• work-summary/2026-02-09-core-pack-jq-elimination.md
• work-summary/2026-02-09-dotenv-parameter-flattening.md
• work-summary/2026-02-action-execution-fixes.md
• work-summary/changelogs/CHANGELOG.md

Verification

• cargo check --all-targets --workspace — zero errors, zero warnings
• cargo test -p attune-worker — all 15 tests pass (including 7 security tests)
• Manual shell script testing — echo.sh, sleep.sh, noop.sh all work correctly with EOF-based reading
• grep -r ATTUNE_PARAMS_END — zero matches remaining in entire project

Current Stdin Protocol (All Runtimes)

{merged_parameters_json}\n
<stdin closed>

• Secrets are merged into the parameters map by the caller before formatting
• Actions receive a single document via readline() or read()
• Shell scripts using DOTENV format read key='value' lines until EOF
• No delimiter, no two-phase protocol, no separate secrets document