Replace the hardcoded isToolMarkupPipe (matching |, ｜, ␂, \x02, !) and
isToolCDATAOpenSeparator (exclusion-based) with a single isToolMarkupSeparator
that treats any Unicode punctuation outside structural characters as a valid
DSML separator. This eliminates the need for a per-character allowlist — novel
separators like ※ are automatically supported without code changes. Also
removes the unused cdataPattern regexp and updates docs to use "non-structural
separator" terminology.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Replace all strings.ToLower usage with ASCII case-insensitive matching
(hasASCIIPrefixFoldAt, indexASCIIFold, hasDSMLPrefix) to prevent slice
bounds errors when Unicode characters change byte length after case
folding (e.g., Turkish İ U+0130 → i + combining dot: 2 bytes → 3 bytes).
Root cause: code created a strings.ToLower(text) copy, found byte
positions in that copy, then used those positions to slice the
original text — byte offsets that were valid in the lowercased copy
became out-of-bounds in the original when case folding changed byte
lengths.
Files changed:
- toolcalls_scan.go: remove 5 lower usages, add hasDSMLPrefix
- toolcalls_parse_markup.go: remove 3 lower usages, add indexASCIIFold
- toolcalls_markup.go: SanitizeLooseCDATA lower removal
- toolcalls_parse.go: updateCDATAStateForStrip lower removal
- tool_prompt.go: align DSML pipe characters with tool call spec
- tool_prompt_test.go: fix pre-existing test character mismatch
The lower parameter was a footgun: callers had to keep it in sync with the
loop bound over text. Instead, skipXMLIgnoredSection now accepts only text
and constructs strings.ToLower(tail) internally for its prefix checks.
This eliminates the entire class of len(text) vs len(lower) boundary bugs
along with the min() workaround.
Also changes:
- findToolCDATAEnd: drop lower param, use text directly for closeMarker
search (]]> is ASCII, ToLower is a no-op for it)
- cdataEndLooksStructural: drop lower param, use raw text byte comparison
- All external callers: loop bound reverts to plain len(text)
The inner tag-matching functions (findXMLStartTagOutsideCDATA,
findMatchingXMLEndTagOutsideCDATA) retain their own local lower for
HasPrefix comparisons against the target tag name, keeping concerns
properly separated.
Fixes#435.
- Add shared ToolMarkupTag scanner (toolcalls_scan.go) replacing hardcoded alias tables
- Support DSML collapsed tag names (<DSMLtool_calls>, <DSMLinvoke>, <DSMLparameter>)
- Parse JSON literal values from parameter bodies (123→number, true→bool, null)
- Recover unclosed CDATA in final parse/flush via SanitizeLooseCDATA
- Align Go and Node implementations (scanToolMarkupTagAt, findMatchingToolMarkupClose)
- Reject bare <invoke> as unsupported syntax, only tool_calls wrapper triggers tool path
- Update API.md and toolcall-semantics.md documentation
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Add support for DSML wrapper aliases (<dsml|tool_calls>, <|tool_calls>,
<｜tool_calls>) alongside canonical XML. Normalize mixed DSML/canonical
tags instead of rejecting them. Add tilde fence (~~~) support, fix
nested fence and unclosed fence handling, support CDATA-protected fence
content, and skip prose mentions when scanning for real tool blocks.
Mirror all changes between Go and Node.js runtimes.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
