MCP tool results used Markdown ATX headings (##/###/####) for section
headers — the status summary, each search hit, every file section in an
exploration — which Markdown-rendering clients (e.g. the Claude Code
VSCode extension) blow up to H1–H4 font size, filling the transcript with
oversized lines (worst on search/explore, where the noise scales with
result count). Swap them all for bold labels, which render at body size
while keeping the same structure. CLI/TTY output (ContextBuilder) is
unchanged — the issue notes it's fine.
The format is parse-coupled, so kept in sync:
- The explore truncation boundary and the offload chunker
(reasoning/reasoner.ts) both key off the per-file header, now a unique
`**`-prefixed marker emitted via a shared fileSectionHeader() helper.
- Updated the offload strip regexes and switched the opt-in report-style
prompt off ATX headings (same client, same rendering issue).
- Updated test helpers (sectionFor, sourcedFiles, the callers
section-boundary scan) that scanned the old markers.
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
## Summary
Completes the explore-overhaul arc: `codegraph_explore` becomes the single primary tool an agent reaches for, and its coverage + output shape are tuned so flow/architecture questions resolve with near-zero Read/Grep.
### What changed
- **explore is the sole primary tool** — removed `codegraph_context` (the fuzzy-input Read-trigger) and `codegraph_trace` (under-picked by agents); explore already surfaces the call flow among the symbols you name. A plain natural-language question now works as the query.
- **Store/handler coverage** — functions defined inside object literals (Zustand `create((set, get) => ({ … }))`, Redux/Pinia/MobX, exported handler/route maps) are indexed as real symbols, including calls through `useStore.getState().fn()` and destructured `const { fn } = useStore.getState()`. A general AST rule, not a per-lib hack.
- **Overload disambiguation** — explore leads with the *right* definition when a method name is overloaded across types (a PascalCase type token in the query biases to that type's own def); `codegraph_node` returns *every* overload's body in one call, with an optional `file`/`line` selector to pin one.
- **Method-atomic render** — explore never returns half a method; at the size budget it drops whole methods/files (and lists what it dropped) instead of truncating a body mid-method.
- **Native-read-shaped output** — per-call output is capped to ~24K with a 25K hard ceiling and concentrated into ~150–250-line flow windows, mirroring how the agent natively reads; repo size scales the *call* budget, not the per-call size (a larger response just gets externalized to a file the host Reads back).
- **Blast radius** folded into explore (dependents + covering tests, locations only).
### Benchmark (refreshed on this build)
Re-validated the 7-repo A/B on 2026-06-02 (Opus 4.8, effort=high, median of 4). WITH arm re-measured on this build, WITHOUT reused:
**~16% cheaper · 47% fewer tokens · 22% faster · 58% fewer tool calls** — 0 file reads on 6 of 7 repos (Gin ~1).
The arc trades larger, cache-heavy explore responses for guaranteed near-zero reads, so cost/token margins soften vs the prior build (Excalidraw and Tokio land at cost break-even) while time and tool-calls stay clear wins everywhere — consistent with the project's stated optimization target (latency + tool-calls, not token cost).
### Validation
- Full suite green: **1112 passed, 2 skipped**.
- 28/28 plain WITH runs across the 7 README repos completed clean; reads median 0 on 6/7.
🤖 Generated with [Claude Code](https://claude.com/claude-code)