Using RTK (Rust Token Killer) with coding-os

Audience: any coding-os user/consumer who also runs RTK — a CLI proxy that compresses command output to cut LLM tokens 60–90%.

TL;DR: RTK is optional and safe to keep, but its compression is lossy by design. Exclude the three commands whose exact output the agent reasons on (grep, rg, sqlite3) so RTK never corrupts coding-os's structural ground truth. Everything else (the big savers) stays.

Why it matters

RTK intercepts Bash tool calls and rewrites them to compressed rtk <cmd> equivalents (filtering / truncating / dedup). For most output (logs, ls, git status, file reads) lossy compression is fine. But for three command classes, lossy = wrong answer:

Command	What lossy compression breaks
`grep` / `rg`	collapses/renames symbols — e.g. `compose_chain` rendered as `n`, identifiers merged. An agent renaming or tracing on that output acts on wrong names.
`sqlite3`	truncates/dedups DB rows — exact values (counts, ids, NULLs) get mangled, so data audits read false numbers.

coding-os leans on exact symbol/row fidelity (graph-first discipline, the search skill's ground-truth counting, doctor DB audits). RTK's lossy filter on those commands silently undermines all three.

Note: RTK does not touch the built-in Read, Grep, Glob tools — those bypass the hook entirely. coding-os already tells agents to prefer those tools over Bash grep/cat (see the search + graph-explorer skills), so a disciplined agent rarely hits RTK at all. The exclusion below protects the cases where Bash is used.

The fix — exclude three commands

Add to RTK's config:

[hooks]
exclude_commands = ["grep", "rg", "sqlite3"]

This preserves ~all of RTK's savings — the bulk comes from rtk read / git / ls (skim-tolerant), which stay proxied.

⚠️ macOS gotcha — edit the RIGHT config file

RTK reads two possible paths, and on macOS the Library one wins (Rust's platform config dir):

Path	macOS active?
`~/Library/Application Support/rtk/config.toml`	✅ yes — this is the `rtk init`-generated config
`~/.config/rtk/config.toml`	usually ignored on macOS

Editing only ~/.config/... has no effect on macOS. Set exclude_commands in the Library file (or both, to be safe). The Library file is the full config ([tracking], [filters], [limits], [hooks], …); its [hooks] exclude_commands defaults to [].

Verify it works (deterministic)

RTK caps a proxied grep at grep_max_results (default 200). So:

# Run a grep that matches >200 lines. If RTK still proxies it, output caps
# at ~200; if excluded, you get the raw full count.
grep -n "e" <a-file-with-300+-lines>.py | wc -l    # >200 => excluded (raw) ✓

Or check rtk gain --history: an excluded grep does not appear (it ran raw, unproxied).

Should I run RTK at all with coding-os?

Optional. coding-os is already token-efficient by design (graph envelopes ~300 tok replace 5–50K-token reads; token-budgeted MCP meta; deferred tool schemas). RTK adds savings on verbose Bash output but is redundant with the Read/Grep tools. If you keep it, apply the exclusion above. If you remove it, nothing in coding-os depends on it.