atomwrite 0.1.2

Atomic file operations CLI for LLM agents — read, write, edit, search, replace with NDJSON output
Documentation
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---
name: atomwrite
description: |
  Use atomwrite for ALL file operations: read, write, edit, search, replace, hash, delete, count, diff, move, copy, list, extract, calc, regex, transform, scope, backup, rollback, apply, batch, completions.
  Auto-invoke when user asks to: write files, search code, replace text, refactor AST, generate regex, calculate expressions, batch operations, check checksums, list project structure, scope code by grammar, backup files, rollback changes, apply patches.
  Trigger on keywords: atomic write, file operation, NDJSON, BLAKE3, checksum, refactor, ast-grep, batch, search parallel, scope, backup, rollback, apply patch, timeout, install completions.
---


# atomwrite
## Core Identity
### REQUIRED
- stdout is ALWAYS NDJSON (one JSON object per line)
- stderr is for logs and tracing only
- Every write goes through the atomic pipeline: tempfile, fsync, rename
- BLAKE3 checksum is present in every write and read response
- Pass `--workspace <DIR>` to set the jail root for all path operations
- All paths are resolved relative to the workspace root
- The `--json` flag is accepted but ignored (output is ALWAYS NDJSON by design)
### FORBIDDEN
- NEVER parse stderr as structured data
- NEVER assume exit 1 is an error (search uses exit 1 for zero matches)
- NEVER write files outside the workspace jail


## Write Operations
### REQUIRED — Atomic Write
- ALWAYS pass `--workspace` flag to define the jail root
- ALWAYS pipe content via stdin
- USE `--backup --retention N` for destructive overwrites
- USE `--expect-checksum <BLAKE3>` for optimistic locking (state drift detection)
- USE `--dry-run` before destructive writes to preview the operation
- USE `--append` to append content to end of existing file
- USE `--prepend` to insert content at beginning of existing file
- USE `--max-size <BYTES>` to limit accepted stdin size
- USE `--line-ending lf|crlf|cr|auto` to normalize line endings (default: auto)
- Response includes `checksum` (BLAKE3) and `bytes_written`
### FORBIDDEN
- NEVER write without `--workspace`
- NEVER pass file content as a CLI argument
### Correct Pattern — Write
```bash
echo "content" | atomwrite --workspace . write target.rs
```
### Correct Pattern — Write with Backup
```bash
cat new_config.toml | atomwrite --workspace . write --backup --retention 3 config.toml
```
### Correct Pattern — Optimistic Locking
```bash
CS=$(atomwrite --workspace . read src/main.rs | jaq -r '.checksum')
echo "updated" | atomwrite --workspace . write --expect-checksum "$CS" src/main.rs
```
### Correct Pattern — Append and Prepend
```bash
echo "// new line" | atomwrite --workspace . write --append src/main.rs
echo "// header" | atomwrite --workspace . write --prepend src/main.rs
```


## Read Operations
### REQUIRED
- USE `read` for file content with metadata
- USE `read --stat` for metadata only (no body)
- USE `read --lines 1:50` for partial reads by line range
- USE `read --line N` to read a single line with optional context via `--context N`
- USE `read --head N` to read the first N lines
- USE `read --tail N` to read the last N lines
- USE `read --format raw` for raw content without JSON envelope
- USE `read --verify-checksum <BLAKE3>` for integrity verification
- Response includes `checksum`, `size`, `lines`
### Correct Pattern — Read
```bash
atomwrite --workspace . read src/main.rs
```
### Correct Pattern — Partial Read
```bash
atomwrite --workspace . read --lines 1:50 src/main.rs
atomwrite --workspace . read --head 20 src/main.rs
atomwrite --workspace . read --tail 10 src/main.rs
```
### Correct Pattern — Line with Context
```bash
atomwrite --workspace . read --line 42 --context 5 src/main.rs
```
### Correct Pattern — Metadata Only
```bash
atomwrite --workspace . read --stat src/main.rs
```


## Search Operations
### REQUIRED
- USE `search` for parallel ripgrep-powered search across files
- Exit code 1 means zero matches found (NOT an error)
- USE `--include '*.rs'` to filter by file extension
- USE `--exclude '*.log'` to exclude files by glob pattern
- USE `--context N` for surrounding lines around each match
- USE `--fixed` (`-F`) for literal string matching (no regex)
- USE `--regex` (`-e`) to explicitly force regex mode
- USE `--word` (`-w`) for word-boundary matching
- USE `--case-insensitive` (`-i`) for case-insensitive search
- USE `--smart-case` (`-S`) for insensitive when pattern is lowercase
- USE `--count` (`-c`) for match counts per file instead of full matches
- USE `--files` (`-l`) for file paths only
- USE `--max-count N` (`-m`) to limit matches per file
- USE `--multiline` (`-U`) for multi-line matching
- USE `--invert` to show lines that do NOT match
- USE `--sort path|modified|created|none` to sort results
- Response is NDJSON with one object per match
### FORBIDDEN
- NEVER treat exit code 1 as a failure in search
### Correct Pattern — Search
```bash
atomwrite --workspace . search 'TODO|FIXME' src/ --include '*.rs'
```
### Correct Pattern — Search with Context
```bash
atomwrite --workspace . search 'unsafe' src/ --context 3
```
### Correct Pattern — Count per File
```bash
atomwrite --workspace . search 'unwrap' src/ --count --sort path
```


## Replace Operations
### REQUIRED
- USE `replace` for bulk text substitution with atomic writes
- ALWAYS use `--dry-run` first for destructive replacements
- USE `--regex` for regex-based patterns
- USE `--word` for word-boundary matching
- USE `--literal` (`-F`) to treat pattern as literal string
- USE `--include '*.rs'` to filter files by extension
- USE `--exclude '*.log'` to exclude files by glob pattern
- USE `--preview` to show diff without writing
- USE `--max-replacements N` (`-n`) to limit replacements per file
- USE `--expect-checksum <BLAKE3>` for optimistic locking
- USE `--backup` to create backup before modifying
- Response includes `matches`, `files_modified`, per-file checksums
### FORBIDDEN
- NEVER run replace without `--dry-run` first
### Correct Pattern — Replace
```bash
atomwrite --workspace . replace --dry-run 'old_api' 'new_api' src/
atomwrite --workspace . replace 'old_api' 'new_api' src/
```
### Correct Pattern — Regex Replace
```bash
atomwrite --workspace . replace --regex 'v\d+\.\d+' 'v2.0' src/ --include '*.toml'
```


## Edit Operations
### REQUIRED
- USE `edit` for surgical modifications by line number or text marker
- USE `--old "text" --new "text"` for exact text replacement (repeatable for multiple)
- USE `--after-line N` for inserting content after a specific line
- USE `--before-line N` for inserting content before a specific line
- USE `--range N:M` for replacing a line range
- USE `--delete-range N:M` for deleting a line range
- USE `--after-match "text"` for inserting content after first match of text
- USE `--before-match "text"` for inserting content before first match
- USE `--between "start" "end"` for replacing content between two markers
- USE `--fuzzy auto|off|aggressive` to control fuzzy matching (default: auto)
- USE `--multi` to apply multiple edits from NDJSON stdin in a single atomic write
- USE `--expect-checksum <BLAKE3>` for optimistic locking
- USE `--line-ending lf|crlf|cr|auto` to normalize line endings
- Pipe new content via stdin when using `--range`, `--after-line`, or `--before-line`
### Correct Pattern — Edit by Text
```bash
atomwrite --workspace . edit src/main.rs --old "old_text" --new "new_text"
```
### Correct Pattern — Multiple Replacements
```bash
atomwrite --workspace . edit src/main.rs --old "foo" --new "bar" --old "baz" --new "qux"
```
### Correct Pattern — Insert After Line
```bash
echo "new_line_content" | atomwrite --workspace . edit src/main.rs --after-line 10
```
### Correct Pattern — Delete Range
```bash
atomwrite --workspace . edit src/main.rs --delete-range 5:10
```
### Correct Pattern — Replace Between Markers
```bash
echo "new block" | atomwrite --workspace . edit src/main.rs --between "// START" "// END"
```
### Correct Pattern — Multiple Edits via NDJSON
```bash
echo '{"old":"foo","new":"bar"}
{"old":"baz","new":"qux"}' | atomwrite --workspace . edit --multi src/main.rs
```


## Transform Operations (AST)
### REQUIRED
- USE `transform` for structural refactoring via ast-grep
- ALWAYS specify `--lang` (`-l`) for the target language
- USE `$NAME` for single AST node captures
- USE `$$$ARGS` for multiple AST node captures (variadic)
- 306 languages supported via ast-grep
- USE `--dry-run` to preview transformations
- USE `--backup` to create backup before modifying
- USE `--include` and `--exclude` to filter files by extension
- Both `--pattern` and `--rewrite` are REQUIRED (no search-only mode)
### Correct Pattern — Transform
```bash
atomwrite --workspace . transform -p 'console.log($$$A)' -r 'logger.info($$$A)' -l js src/
```
### Correct Pattern — Rust Refactor
```bash
atomwrite --workspace . transform -p '$EXPR.unwrap()' -r '$EXPR?' -l rust src/
```
### Correct Pattern — Dry Run
```bash
atomwrite --workspace . transform --dry-run -p 'old_fn($$$A)' -r 'new_fn($$$A)' -l rust src/
```


## Scope Operations (Grammatical Scoping)
### REQUIRED
- USE `scope` to select AST categories and apply actions on matched code
- ALWAYS specify `--lang` for the target language
- USE `--query` for prepared queries by language (see list below)
- USE `--pattern` for custom AST patterns
- USE `--delete` to remove matched content
- USE `--action upper|lower|titlecase|squeeze` for text transformations
- USE `--replace-with "text"` for custom replacement
- USE `--include '*.rs'` to filter files by extension
- USE `--exclude '*.log'` to exclude files by glob pattern
- USE `--backup` to create backup before modifying
- USE `--dry-run` to preview changes
### Prepared Queries — Rust
- `comments`, `doc-comment`, `strings`
- `fn`, `pub-fn`, `async-fn`, `unsafe-fn`, `test-fn`
- `struct`, `pub-struct`, `enum`, `pub-enum`
- `trait`, `impl`, `mod`, `use`
- `closure`, `unsafe`, `attribute`, `derive`
- `return`, `match`, `if-let`, `while-let`
- `for`, `loop`, `const`, `static`
- `type-alias`, `macro-rules`
### Prepared Queries — Python
- `comments`, `strings`
- `class`, `def`, `async-def`, `lambda`
- `import`, `from-import`
- `with`, `for`, `while`
- `decorator`, `try-except`
### Prepared Queries — JavaScript and TypeScript
- `comments`, `strings`
- `fn`, `arrow-fn`, `async-fn`
- `class`, `import`, `export`
- `try-catch`, `const`, `let`
### Prepared Queries — Go
- `fn`, `struct`, `interface`
- `goroutine`, `defer`, `import`
- `const`, `var`
### Correct Pattern — Scope
```bash
atomwrite --workspace . scope src/ --lang rust --query comments --delete --dry-run
atomwrite --workspace . scope src/ --lang rust --query fn --action upper --dry-run
atomwrite --workspace . scope src/ --lang python --query def --action lower
```


## Batch Operations
### REQUIRED
- USE `batch` for multiple operations in a single call
- Input is NDJSON on stdin (one JSON object per line)
- Each line requires an `op` field: `write`, `replace`, `delete`, `edit`, `move`, `copy`, `hash`
- For `move` and `copy`: use `source` field (origin) and `target` field (destination)
- USE `--file <PATH>` to read manifest from file instead of stdin
- USE `--transaction` for all-or-nothing execution with automatic rollback on failure
- USE `--dry-run` to preview the entire batch
- USE `--input-schema` to get the JSON Schema for the input manifest format
- Response is NDJSON with one result per operation
### Correct Pattern — Batch with Write and Delete
```bash
echo '{"op":"write","target":"a.txt","content":"hello"}
{"op":"delete","target":"tmp.log"}' | atomwrite --workspace . batch
```
### Correct Pattern — Batch with Move and Copy
```bash
echo '{"op":"move","source":"src/old.rs","target":"src/new.rs"}
{"op":"copy","source":"src/template.rs","target":"src/module.rs"}' | atomwrite --workspace . batch
```
### Correct Pattern — Transactional Batch
```bash
cat ops.ndjson | atomwrite --workspace . batch --transaction --dry-run
cat ops.ndjson | atomwrite --workspace . batch --transaction
```
### Correct Pattern — Batch from File
```bash
atomwrite --workspace . batch --file ops.ndjson --transaction
```


## Hash Operations
### REQUIRED
- USE `hash` for standalone BLAKE3 checksums
- Accepts one or more file paths
- USE `--verify <BLAKE3>` to check file hash against expected value
- USE `--stdin` to hash content from stdin
- USE `--recursive` (`-r`) to hash directories recursively
- Response includes `path` and `checksum` per file
### Correct Pattern — Hash
```bash
atomwrite --workspace . hash src/main.rs
atomwrite --workspace . hash src/*.rs
atomwrite --workspace . hash --verify abc123 src/main.rs
echo "content" | atomwrite hash --stdin
```


## Delete Operations
### REQUIRED
- USE `delete` for atomic file removal
- USE `--backup --retention N` to keep backups before deletion
- USE `--recursive` (`-r`) to remove directories recursively
- USE `--include '*.log'` to filter by extension
- USE `--exclude '*.rs'` to exclude by extension
- USE `--yes` (`-y`) to skip confirmation
- USE `--dry-run` to preview
### Correct Pattern — Delete
```bash
atomwrite --workspace . delete --backup --retention 1 tmp/scratch.rs
atomwrite --workspace . delete --recursive --include '*.log' --dry-run logs/
```


## Diff Operations
### REQUIRED
- USE `diff` for comparing two files
- USE `--unified` for unified diff format
- USE `--stat` for summary statistics only
- USE `--context N` (`-C`) for context lines in diff (default: 3)
- USE `--algorithm myers|patience|lcs` to choose diff algorithm (default: patience)
- Response includes structured NDJSON diff hunks
### Correct Pattern — Diff
```bash
atomwrite --workspace . diff src/old.rs src/new.rs
atomwrite --workspace . diff --stat src/old.rs src/new.rs
atomwrite --workspace . diff --unified --context 5 src/old.rs src/new.rs
```


## Move and Copy Operations
### REQUIRED
- USE `move` for atomic rename/move within the workspace
- USE `copy` for atomic copy with checksum verification
- Both respect the workspace jail
- USE `--force` to overwrite destination if it exists
- USE `--dry-run` to preview
- USE `--backup` to backup destination if it exists
- `copy` accepts `--recursive` for directories and `--preserve` for timestamps
### Correct Pattern — Move
```bash
atomwrite --workspace . move src/old.rs src/new.rs
atomwrite --workspace . move --force src/old.rs src/existing.rs
```
### Correct Pattern — Copy
```bash
atomwrite --workspace . copy src/template.rs src/new_module.rs
atomwrite --workspace . copy --recursive --preserve src/dir/ dest/dir/
```


## List Operations
### REQUIRED
- USE `list` for directory and file listing
- USE `--include '*.rs'` to filter by extension
- USE `--exclude '*.log'` to exclude by extension
- USE `--long` for size and modification time
- USE `--depth N` to limit directory depth
- USE `--count-by-ext` for file count grouped by extension
- USE `--all` to include hidden files
### Correct Pattern — List
```bash
atomwrite --workspace . list --include '*.rs' src/
atomwrite --workspace . list --long --depth 2 src/
atomwrite --workspace . list --count-by-ext src/
atomwrite --workspace . list --all --long src/
```


## Count Operations
### REQUIRED
- USE `count` for file and line counting
- USE `--by-extension` to group counts by file extension
- USE `--by-size` with `--top N` to list largest files
- USE `--include` and `--exclude` to filter
- Response includes `files`, `lines`, `bytes`
### Correct Pattern — Count
```bash
atomwrite --workspace . count --include '*.rs' src/
atomwrite --workspace . count --by-extension src/
atomwrite --workspace . count --by-size --top 20 src/
```


## Extract Operations
### REQUIRED
- USE `extract` for NDJSON field extraction from piped input
- Pass field names as positional arguments to select specific JSON fields
- USE `--delimiter <SEP>` for text mode with custom separator
### Correct Pattern — Extract
```bash
atomwrite --workspace . search 'TODO' src/ | atomwrite extract path line_number
```


## Calc Operations
### REQUIRED
- USE `calc` for math expressions and unit conversions
- ALWAYS quote the expression
- USE `--stdin` to read expressions from stdin (one per line)
- No `--workspace` needed (stateless)
### Correct Pattern — Calc
```bash
atomwrite calc "2 hours + 30 minutes to seconds"
atomwrite calc "1.5 GiB to bytes"
atomwrite calc "sqrt(144) + 2^10"
```


## Regex Operations
### REQUIRED
- USE `regex` for generating regex from examples
- Pass 3+ examples for accurate patterns
- USE `--digits` (`-d`) for `\d` generalization
- USE `--words` (`-w`) for `\w` generalization
- USE `--spaces` (`-s`) for `\s` generalization
- USE `--repetitions` (`-r`) to detect repetitions
- USE `--case-insensitive` (`-i`) for case-insensitive matching
- USE `--no-anchors` to remove `^` and `$` from result
- USE `--stdin` to read examples from stdin (one per line)
- No `--workspace` needed (stateless)
### Correct Pattern — Regex
```bash
atomwrite regex "192.168.1.1" "10.0.0.255" --digits
atomwrite regex "v1.0.0" "v2.1.3" "v10.0.1" --digits
atomwrite regex -d -w -s -r "example1" "example2"
```


## Backup Operations
### REQUIRED
- USE `backup` to create timestamped backups with BLAKE3 checksums
- USE `--retention N` to control how many backups to keep (default: 5)
- USE `--output-dir <DIR>` to direct backups to a specific directory
- USE `--dry-run` to preview
### Correct Pattern — Backup
```bash
atomwrite --workspace . backup src/config.toml
atomwrite --workspace . backup src/main.rs src/lib.rs --retention 3
atomwrite --workspace . backup src/main.rs --output-dir /tmp/backups/
```


## Rollback Operations
### REQUIRED
- USE `rollback` to restore a file from a previous backup
- USE `--latest` to restore the most recent backup (default)
- USE `--timestamp YYYYMMDD_HHMMSS` to restore a specific backup
- USE `--verify` to check BLAKE3 checksum after restoration
- USE `--dry-run` to preview
### Correct Pattern — Rollback
```bash
atomwrite --workspace . rollback src/config.toml
atomwrite --workspace . rollback src/config.toml --timestamp 20260530_120000 --verify
```


## Apply Operations (Patch)
### REQUIRED
- USE `apply` to apply patches from stdin to a target file
- Auto-detects patch format: unified diff, SEARCH/REPLACE blocks, markdown-fenced, full file
- USE `--format auto|unified|search-replace|full|markdown` to force format
- USE `--backup` to create backup before patching
- USE `--dry-run` to preview
### Correct Pattern — Apply
```bash
echo "new content" | atomwrite --workspace . apply src/file.txt --format full
git diff src/file.txt | atomwrite --workspace . apply src/file.txt
```


## Completions
### REQUIRED
- USE `completions` to generate shell completions
- Supports `bash`, `zsh`, `fish`, `elvish`, `powershell`
### Correct Pattern — Completions
```bash
atomwrite completions bash > ~/.local/share/bash-completion/completions/atomwrite
atomwrite completions zsh > ~/.zfunc/_atomwrite
```


## Common Pipelines
### Correct Pattern — Optimistic Locking (Read, Modify, Write)
```bash
CS=$(atomwrite --workspace . read src/config.rs | jaq -r '.checksum')
echo "new content" | atomwrite --workspace . write --expect-checksum "$CS" src/config.rs
```
### Correct Pattern — Search and Extract Fields
```bash
atomwrite --workspace . search 'TODO' src/ --include '*.rs' | atomwrite extract path line_number
```
### Correct Pattern — Hash for Auditing
```bash
atomwrite --workspace . hash src/main.rs src/lib.rs | jaq -r '.checksum'
```
### Correct Pattern — Structured Diff
```bash
atomwrite --workspace . diff src/old.rs src/new.rs | jaq '.type'
```
### Correct Pattern — Transactional Batch with Verification
```bash
cat ops.ndjson | atomwrite --workspace . batch --transaction --dry-run
cat ops.ndjson | atomwrite --workspace . batch --transaction
```


## Error Handling
### REQUIRED
- CHECK exit code first before parsing stdout
- PARSE stdout JSON when `error: true` for structured error details
- USE `error_class` to determine retry strategy
- RETRY when `retryable: true`
- USE `suggestion` field for actionable remediation
### FORBIDDEN
- NEVER ignore non-zero exit codes (except exit 1 in search)
- NEVER parse stderr for error data
- NEVER retry when `retryable: false`
### Correct Pattern — Error Handling
```bash
output=$(atomwrite --workspace . read missing.txt 2>/dev/null)
exit_code=$?
if [ $exit_code -ne 0 ]; then
  echo "$output" | jaq '{code: .code, class: .error_class, suggestion: .suggestion}'
fi
```


## Exit Codes
### REQUIRED — Full Reference
- `0` — success
- `1` — no matches (search/replace found zero results, NOT an error)
- `4` — not found (file or directory does not exist)
- `13` — permission denied
- `28` — disk full
- `30` — quota exceeded
- `65` — invalid input (malformed arguments or content)
- `73` — cross-device (move across filesystem boundaries)
- `74` — I/O error (generic filesystem failure)
- `78` — config invalid (malformed configuration)
- `82` — state drift (checksum mismatch, optimistic locking failed)
- `85` — FIFO detected (named pipe cannot be atomically written)
- `86` — device file detected (block or character device)
- `126` — workspace jail violation (path escapes workspace root)
- `127` — symlink blocked (symlink target outside workspace)
- `128` — immutable (file marked immutable)
- `130` — SIGINT (interrupted by user)
- `141` — SIGPIPE (broken pipe)
- `143` — SIGTERM (terminated by signal)
- `255` — internal error (unexpected failure)


## Error JSON Schema
### REQUIRED — Fields
- `error` (bool) — always `true` when an error occurs
- `code` (string) — machine-readable error code
- `exit` (u8) — exit code number
- `message` (string) — human-readable description
- `path` (string, optional) — file path involved in the error
- `error_class` (string) — one of: `permanent`, `transient`, `conflict`, `precondition_failed`
- `retryable` (bool) — whether the operation can be retried
- `suggestion` (string, optional) — actionable remediation step


## Global Flags
### REQUIRED — Reference
- `--workspace <DIR>` — set the workspace jail root (REQUIRED for file operations)
- `--max-filesize <BYTES>` — maximum accepted file size in bytes (default: 1 GiB)
- `--threads <N>` / `-j` — number of parallel threads (0 = all cores, env: `RAYON_NUM_THREADS`)
- `--json-schema` — print the output JSON schema for any subcommand
- `--json` — accepted for compatibility but ignored (output is ALWAYS NDJSON)
- `--color auto|always|never` — control colored output
- `--no-color` — disable colored output (equivalent to `--color never`)
- `--no-gitignore` — do not respect `.gitignore` files
- `--hidden` — include hidden files and directories
- `--follow-symlinks` — follow symbolic links during traversal
- `--verbose` / `-v` — increase log verbosity on stderr (-v info, -vv debug, -vvv trace)
- `--quiet` / `-q` — decrease verbosity (-q error, -qq off)
- `--lang <LOCALE>` — override display locale (en, pt-BR) via `ATOMWRITE_LANG` env


## JSON Schema Introspection
### REQUIRED
- USE `--json-schema` flag to get the output schema for any subcommand
- USE schema output for programmatic validation of responses
### Correct Pattern — Schema
```bash
atomwrite write --json-schema
atomwrite search --json-schema
```