---
name: trustabl-pre-coding
description: >-
  Pre-coding reliability constraints, used for writing and reviewing agent definitions with: claude_sdk, openai_sdk
allowed-tools: Read
disable-model-invocation: false
---

# Trustabl Pre-Coding Reliability Constraints

<!-- generated: 2026-01-01 | rules: abc1234 | schema: 13 | sdks: claude_sdk, openai_sdk | template: 2 -->

Before writing any agent code, apply every constraint below. Rules are
ordered by severity. A violation here will fire the corresponding finding
in post-build scan — prevent it now.

## How to Apply These Constraints

Work against this document; do not assume a definition is correct because it
looks right. After writing or changing any tool, agent, subagent, or skill
definition, run this loop before moving on.

1. CHECK YOUR WORK
   Re-read the definition you just wrote against every constraint in this
   document whose "When this applies" matches it. Check explicitly — do not
   assume the constraint was satisfied.

2. NAME THE VIOLATION
   State the specific rule ID, not "this looks wrong". "CSDK-005 — this tool
   raises without a structured error contract" is actionable; "error handling
   needs work" is not. If nothing matches, the definition passes; move on.

3. MATCH THE REPAIR TO THE VIOLATION
   Apply that rule's own Directive. Where the repair goes is set by scope,
   and how to proceed is set by severity:

     tool   → change the tool definition
     agent  → change the agent constructor call
     repo   → change project configuration, not code

     critical / high  → make the change, then state which rule required it
     medium / low     → apply the directive directly

   If the Directive cannot be applied as written — it conflicts with another
   constraint here, or the fix is outside the file you are editing — stop and
   say so rather than approximating it.

4. KEEP A TRAIL
   Note the rule ID and the change that cleared it. Do not reintroduce a
   pattern you already repaired in this session, and do not re-apply a repair
   that did not clear the violation — report it instead.

Scope: this loop applies to agent, tool, subagent, and skill definitions —
the surfaces the constraints below govern. It is not a general code-review
procedure.

---

## Claude Agent SDK

### Tool Rules

---

#### [CSDK-001] Claude subagent tool function has no docstring
**Severity:** medium | **Confidence:** 0.90

**Directive:** Add a docstring describing what the tool does, its parameters, and return value.

**Why:** Missing docstring means the model cannot read the tool's intent.

**When this applies:** When defining a tool.

### Agent Rules

---

#### [CSDK-101] Claude subagent is granted the Bash tool without restrictions
**Severity:** high | **Confidence:** 0.80

**Directive:** Add input guardrails or restrict tool grants to exact prefixes.

**Why:** An agent with unrestricted Bash access poses a high risk.

**When this applies:** When declaring an agent.

---

## OpenAI Agents SDK

### Tool Rules

---

#### [OAI-001] Tool function has no docstring
**Severity:** low | **Confidence:** 0.90

**Directive:** Add a docstring to every @function_tool decorated function.

**Why:** The docstring is the model-facing description; without it the model cannot use the tool correctly.

**When this applies:** When defining a tool.