Operations

chimera.core.operations defines four Protocol interfaces for the low-level I/O operations used by built-in tools. Swapping in a custom implementation lets tools work against Docker containers, remote servers, or in-memory fixtures.

Protocols

Protocol	Methods	Description
ReadOps	read_file(path), file_exists(path)	File reading backend
WriteOps	write_file(path, content)	File writing backend
BashOps	run_command(command, timeout, cwd)	Command execution backend
SearchOps	search_files(pattern, path), list_files(pattern)	File search backend

All four are @runtime_checkable, so isinstance() checks work without subclassing.

Local implementations

Class	Protocol	Notes
LocalReadOps	ReadOps	open() relative to cwd
LocalWriteOps	WriteOps	mkdir -p before writing
LocalBashOps	BashOps	subprocess.run(shell=True), returns CommandResult
LocalSearchOps	SearchOps	Path.rglob with regex matching

Each constructor accepts an optional cwd: str = "." argument.

Example — custom ops for Docker

from chimera.core.operations import ReadOps, BashOps
from chimera.types import CommandResult

class DockerReadOps:
    def __init__(self, container: str) -> None:
        self.container = container

    def read_file(self, path: str) -> str:
        import subprocess
        return subprocess.check_output(
            ["docker", "exec", self.container, "cat", path], text=True
        )

    def file_exists(self, path: str) -> bool:
        import subprocess
        r = subprocess.run(
            ["docker", "exec", self.container, "test", "-f", path]
        )
        return r.returncode == 0

# Pass to tools that accept a read_ops parameter
from chimera.tools import ReadTool
tool = ReadTool(read_ops=DockerReadOps("my-container"))

CommandResult

BashOps.run_command returns a CommandResult (from chimera.types):

Field	Type	Description
stdout	str	Standard output
stderr	str	Standard error
exit_code	int	Process exit code (-1 on timeout)