Custom Operator Tools (`[[tool]]` extension points)

Status: Open — jackin-exec, the credential picker, and MCP execution primitives exist as reusable building blocks; the operator-configured [[tool]] surface itself has no config parsing, no keybinding registration, and no firing/substitution code yet (Phase 2, Agent Orchestration Program)

Shipped baseline

jackin❯ has in-container jackin-exec (crates/jackin-capsule/src/exec.rs, crates/jackin-runtime/src/exec_host.rs), a credential picker (crates/jackin-env/src/picker.rs), and MCP execution plumbing (crates/jackin-capsule/src/mcp_server.rs). These are the primitives a [[tool]] surface would reuse, but none of them expose an operator-configurable hotkey-to-command mechanism today. There is no [[tool]] array in config parsing, no reserved-key validation for custom tools, and no substitution/firing code in the console or capsule TUI.

Remaining work

1. [[tool]] config array (operator-config level): type = "exec" | "prompt", key, name, exec/prompt, optional scope role filter.
2. Reserved-key collision detection at config load.
3. Substitution engine for {instance}, {workspace}, {workdir}, {host_workdir}, {input}, and tag-protocol values ({repo}, {issue}, {pr}, {link}) once agent tag protocol ships.
4. Console keybinding registration and output-capture rendering (modal for V1).
5. Tool firing routed through the operator handler system once that command-resolution layer exists.

Out of scope (for now)

• Per-workspace tool overrides — operator-config-level only.
• Streaming output for long-running tools — capture-and-display-on-completion only.
• Tool authoring helpers, tool emission of <jackin:*> tags, tool composability.

Related work

• Research: Custom Operator Tools: Design Exploration — multicode's [[tool]] design, recommended config shape, and open questions.
• Operator handler system — shared command-resolution machinery this item will route through.
• Agent tag protocol — source of {repo}, {issue}, {pr}, {link} substitutions.
• Console resource panel — infrastructure a future scrolling tool-output log would need.