kastell-research

Kastell Research

Purpose

Explore the Kastell codebase using read-only tools (Read, Grep, Glob). Runs in a forked Explore agent with Kastell architecture knowledge inlined.

When to Use

• Bug investigation: Trace a bug from CLI command through core logic to adapters/providers. Start at the command file, follow imports to core, check utils and adapters.
• Feature mapping: Map all callsites of a function, trace the import chain, understand how subsystems connect before making changes.
• Architecture question: Understand how audit categories work, how the adapter dispatch flows, or how lock hardening steps are structured.

Live Codebase

Commands: !node -e "import('fs').then(f=>console.log(f.readdirSync('src/commands').filter(x=>x.endsWith('.ts')).map(x=>x.replace('.ts','')).join(', '))).catch(()=>console.log('commands dir not found'))" Provider registry: !node -e "import('fs').then(f=>{const c=f.readFileSync('src/constants.ts','utf8');const m=c.match(/PROVIDER_REGISTRY[\s\S]{0,200}/);console.log(m?m[0].split('\n').slice(0,4).join('\n'):'not found')}).catch(()=>console.log('constants.ts not found'))"

Architecture Map

src/
  commands/     # 31 thin CLI wrappers (parse args + delegate only)
  core/         # Business logic (ALL computation here)
    audit/      # 30 audit categories, 457+ checks
    lock/       # 24-step server hardening
  providers/    # Cloud API: hetzner, digitalocean, vultr, linode
  adapters/     # Platform abstraction: coolify, dokploy
    factory.ts  # getAdapter(platform) — entry point
  mcp/
    server.ts   # 13 tool registrations
    tools/      # Handler files
  utils/        # ssh, config, cloudInit, modeGuard
  types/        # ServerMode, ServerRecord, Platform
  constants.ts  # PROVIDER_REGISTRY

Layer Flow

Commands (parse args) --> Core (business logic) --> Providers (cloud API) / Adapters (platform ops). MCP tools also delegate to Core.

Research Workflows

Bug investigation:

1. Find the command file (src/commands/<name>.ts)
2. Follow the core import (src/core/<name>.ts)
3. Check adapter/provider calls
4. Check utils (ssh, config)

Feature mapping:

1. Grep for the function name
2. Follow import chain
3. Map all callsites
4. Check test coverage in __tests__/

Architecture question:

1. Read the Architecture Map above
2. Read kastell-plugin/skills/kastell-ops/SKILL.md for full detail (adapter contract, provider registry, layer rules)
3. Trace specific files

Debug by Symptom

Common failure patterns and where to look first:

Symptom	Start Here	Then Check
SSH auth failure	src/utils/ssh.ts → sshExec()	assertValidIp(), server config ~/.kastell/servers.json, banner parsing
Provider API error	src/providers/<name>.ts	withProviderErrorHandling() in src/utils/retry.ts, API token config
Audit check false positive	src/core/audit/checks/<category>.ts	SSH command output parsing, regex pattern, sshExec mock in test
Fix rejected (SAFE tier)	src/core/fix.ts → resolveTier()	FORBIDDEN_PATTERNS, shell redirect/pipe in fixCommand string
MCP tool error	src/mcp/tools/<name>.ts	Handler → core delegation, Zod schema validation, result.content format
Lock step failure	src/core/lock.ts	Step's SSH command, sshExec stderr, cloud-init completion
Config not found	src/utils/config.ts	~/.kastell/ dir existence, servers.json format, migration from ~/.quicklify/

Known pitfalls: See kastell-plugin/skills/kastell-ops/references/pitfalls.md

ARGUMENTS

$ARGUMENTS