# Cross Border Streamer Tax Legal Advisor Agent Skill

> A Claude skill from dungnotnull/cross-border-streamer-tax-legal-advisor-agent-skill.

- **Type:** Skill
- **Install:** `agentstack add skill-dungnotnull-cross-border-streamer-tax-legal-advisor-agent-skill-cross-border-streamer-tax-legal-advisor-agent-skill`
- **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior
- **Seller:** [dungnotnull](https://agentstack.voostack.com/s/dungnotnull)
- **Installs:** 0
- **Category:** [Agent Skills](https://agentstack.voostack.com/c/agent-skills)
- **Latest version:** 0.1.0
- **License:** MIT
- **Upstream author:** [dungnotnull](https://github.com/dungnotnull)
- **Source:** https://github.com/dungnotnull/cross-border-streamer-tax-legal-advisor-agent-skill

## Install

```sh
agentstack add skill-dungnotnull-cross-border-streamer-tax-legal-advisor-agent-skill-cross-border-streamer-tax-legal-advisor-agent-skill
```

Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent.

## About

# SKILL.md — Skill Registry (cross-border-streamer-tax-legal-advisor)

> **Single source of truth** for how skills are registered, resolved, executed, and validated in the runtime engine. Generated from the live `SkillRegistry` via `scripts/generate_manifest.py`; the machine-readable twin lives at `assets/schemas/skill_manifest.json`.

This skill ships **two parallel, equivalent layers** that share one deterministic backbone (`tools/tax_data.py`) and one knowledge base (`SECOND-KNOWLEDGE-BRAIN.md`):

| Layer | Purpose | Location |
|-------|---------|----------|
| Declarative (markdown) | Claude Code reasoning persona, prompts, gates | `skills/*.md` |
| Runtime (registry) | Programmatic orchestration: registry, router, hooks, tools, engine | `agent/` |

Both layers emit the same 6-step pipeline guarded by the same 10 quality gates (U1–U6 + G1–G4) and the same 4-verdict contract.

## 1. How a skill is registered

A skill is a subclass of `agent.base.Skill` exposing a frozen `SkillManifest` (name, description, version, step, input/output JSON schemas, the tools it may call, and its quality gate) and an `execute(ctx, state)` method. Registration goes through `SkillRegistry`:

```python
from agent.skills import build_default_registry
reg = build_default_registry()        # default toolset + 6 skills
reg.register_tool(MyTool())           # add a custom tool
reg.register_skill(MySkill())         # add a custom skill (step-ordered)
reg.validate_manifests()              # every schema is well-formed
```

Registration invariants enforced by `SkillRegistry`:
- unique skill name and unique step index;
- every tool referenced in `manifest.tools` must already be registered;
- `validate_manifests()` checks each input/output schema is itself a valid JSON-Schema subset.

## 2. How a request is resolved

`agent.router.ChainOfThoughtRouter.plan()` inspects the request and returns an ordered execution plan (one entry per skill invocation):
- **combined** (default): the full 6-step pipeline in order;
- **focused** (`residency` / `withholding` / `vat` / `deductions` / `ip`): the same pipeline with the core step narrowed to the focus;
- **comparison**: runs `sub-core-analysis` once per case payload.
An unknown `analysis_type` degrades to `combined` with an explicit assumption recorded on `RunState` — the router never invents steps.

## 3. How a skill is executed

`Skill.safe_execute(ctx, state)` wraps `execute` with:
1. input validation against `manifest.input_schema`; on failure it records a limitation, escalates degradation to Level 3, and returns an error dict (never raises to the engine);
2. the `execute` call, which mutates `RunState` (limitations, degradation, retries, events) and returns an output dict;
3. output validation against `manifest.output_schema`; a schema mismatch is recorded as a limitation but the partial output is preserved.

`Tool.safe_execute` follows the same contract for individual tool calls, returning a `ToolResult(ok, value, error, source)`.

## 4. How everything is validated

- **Manifests**: `SkillRegistry.validate_manifests()` — every skill's input/output schema is a well-formed JSON-Schema subset.
- **I/O**: `agent.base.validate_instance` — a dependency-free validator for `type/required/properties/enum/items/additionalProperties/minimum/maximum/minItems/oneOf`, applied on every tool and skill boundary.
- **Project contract**: `tools/validate_project.py` — the 8-File Contract + cross-file integrity + encoding + phase-tracker checks.
- **Deterministic data**: `scripts/seed_tax_data.py` — referential integrity of `tax_data.py` (treaty jurisdictions exist, rates in range, verdict set matches the contract).

## 5. Registered skills

| Step | Skill | Tools | Quality gate |
|------|-------|-------|--------------|
| 1 | `sub-gather-requirements` | language_detect, jurisdictions_list | at least one object + residency jurisdiction confirmed |
| 2 | `sub-evidence-collector` | residency_lookup, withholding_lookup, vat_lookup, platform_lookup, form_1099k_threshold, knowledge_brain_query | at least current data + 1 authoritative document, or limitat |
| 3 | `sub-core-analysis` | residency_lookup, withholding_lookup, vat_lookup, platform_lookup, deductions_list, ip_risks_list | residency/PE assessed; withholding & treaty mapped; VAT addr |
| 4 | `sub-knowledge-updater` | knowledge_brain_query, jurisdictions_list | at least 1 academic/authoritative source surfaced; coverage  |
| 5 | `sub-advisor` | knowledge_brain_query | conclusion is exactly one declared verdict; disclosure prece |
| 6 | `quality-gate` | — | all gates pass or carry an explicit limitation notice |

### sub-gather-requirements (step 1)

_Clarify object, constraints, timeframe, inputs, audience, language._  ·  **version** 2.0.0

**Input schema:**
```json
{
  "type": "object",
  "required": [
    "query"
  ],
  "properties": {
    "query": {
      "type": "string"
    },
    "platforms": {
      "type": "array",
      "items": {
        "type": "string"
      }
    },
    "resident_jurisdiction": {
      "type": "string"
    },
    "source_jurisdictions": {
      "type": "array",
      "items": {
        "type": "string"
      }
    },
    "income_usd": {
      "type": [
        "number",
        "null"
      ]
    },
    "days_present": {
      "type": [
        "integer",
        "null"
      ]
    },
    "year": {
      "type": "integer"
    },
    "language": {
      "type": "string",
      "enum": [
        "en",
        "vi"
      ]
    },
    "analysis_type": {
      "type": "string"
    }
  }
}
```
**Output schema:**
```json
{
  "type": "object",
  "required": [
    "requirements",
    "assumptions",
    "missing_decisive"
  ],
  "properties": {
    "requirements": {
      "type": "object"
    },
    "assumptions": {
      "type": "array",
      "items": {
        "type": "string"
      }
    },
    "missing_decisive": {
      "type": "array",
      "items": {
        "type": "string"
      }
    }
  }
}
```

### sub-evidence-collector (step 2)

_Fetch authoritative real-time + reference data with tier labels._  ·  **version** 2.0.0

**Input schema:**
```json
{
  "type": "object",
  "required": [
    "upstream"
  ],
  "properties": {
    "upstream": {
      "type": "object"
    }
  }
}
```
**Output schema:**
```json
{
  "type": "object",
  "required": [
    "evidence",
    "degradation_level"
  ],
  "properties": {
    "evidence": {
      "type": "object",
      "required": [
        "current_data",
        "authoritative_docs",
        "recent_news",
        "reference_benchmarks"
      ],
      "properties": {
        "current_data": {
          "type": "array"
        },
        "authoritative_docs": {
          "type": "array"
        },
        "recent_news": {
          "type": "array"
        },
        "reference_benchmarks": {
          "type": "array"
        }
      }
    },
    "degradation_level": {
      "type": "integer",
      "minimum": 0,
      "maximum": 4
    },
    "substituted_sources": {
      "type": "array",
      "items": {
        "type": "string"
      }
    }
  }
}
```

### sub-core-analysis (step 3)

_Residency/PE, withholding & treaty, VAT/GST, deductions, IP, scenarios._  ·  **version** 2.0.0

**Input schema:**
```json
{
  "type": "object",
  "required": [
    "upstream"
  ],
  "properties": {
    "upstream": {
      "type": "object"
    },
    "analysis_type": {
      "type": "string"
    },
    "comparison_case": {
      "type": "object"
    },
    "case_index": {
      "type": "integer"
    }
  }
}
```
**Output schema:**
```json
{
  "type": "object",
  "required": [
    "income_inventory",
    "residency",
    "withholding",
    "vat",
    "deductions",
    "ip_risks",
    "scenarios"
  ],
  "properties": {
    "income_inventory": {
      "type": "array"
    },
    "residency": {
      "type": "object"
    },
    "withholding": {
      "type": "array"
    },
    "vat": {
      "type": "array"
    },
    "deductions": {
      "type": "array"
    },
    "ip_risks": {
      "type": "array"
    },
    "scenarios": {
      "type": "array"
    }
  }
}
```

### sub-knowledge-updater (step 4)

_Query the knowledge base; surface citations; flag crawl gaps._  ·  **version** 2.0.0

**Input schema:**
```json
{
  "type": "object",
  "required": [
    "upstream"
  ],
  "properties": {
    "upstream": {
      "type": "object"
    }
  }
}
```
**Output schema:**
```json
{
  "type": "object",
  "required": [
    "citations",
    "gaps",
    "coverage"
  ],
  "properties": {
    "citations": {
      "type": "array"
    },
    "gaps": {
      "type": "array",
      "items": {
        "type": "string"
      }
    },
    "coverage": {
      "type": "string",
      "enum": [
        "Strong",
        "Moderate",
        "Weak"
      ]
    }
  }
}
```

### sub-advisor (step 5)

_Synthesize a risk-disclosed verdict with evidence chain + remediation._  ·  **version** 2.0.0

**Input schema:**
```json
{
  "type": "object",
  "required": [
    "upstream"
  ],
  "properties": {
    "upstream": {
      "type": "object"
    }
  }
}
```
**Output schema:**
```json
{
  "type": "object",
  "required": [
    "verdict",
    "scenarios",
    "key_risks",
    "evidence_chain",
    "remediation",
    "disclosure"
  ],
  "properties": {
    "verdict": {
      "type": "string",
      "enum": [
        "Compliant Plan",
        "Conditional (documentation)",
        "Compliance Risk",
        "Inconclusive"
      ]
    },
    "scenarios": {
      "type": "array"
    },
    "key_risks": {
      "type": "array"
    },
    "evidence_chain": {
      "type": "array"
    },
    "remediation": {
      "type": "array",
      "items": {
        "type": "string"
      }
    },
    "disclosure": {
      "type": "string"
    }
  }
}
```

### quality-gate (step 6)

_Enforce U1-U6 + G1-G4 gates with auto-fix + 2-retry enforcement._  ·  **version** 2.0.0

**Input schema:**
```json
{
  "type": "object",
  "required": [
    "upstream"
  ],
  "properties": {
    "upstream": {
      "type": "object"
    }
  }
}
```
**Output schema:**
```json
{
  "type": "object",
  "required": [
    "gates",
    "limitations",
    "degradation_level"
  ],
  "properties": {
    "gates": {
      "type": "object"
    },
    "limitations": {
      "type": "array",
      "items": {
        "type": "string"
      }
    },
    "degradation_level": {
      "type": "integer",
      "minimum": 0,
      "maximum": 4
    }
  }
}
```

## 6. Registered tools

| Tool | Description |
|------|-------------|
| `residency_lookup` | Assess tax residency for a jurisdiction via the statutory day-count test. |
| `withholding_lookup` | Compute effective withholding (default + treaty-capped) for a source->resident pair. |
| `vat_lookup` | Return the VAT/GST rule for a jurisdiction (rate, threshold, mechanism). |
| `platform_lookup` | Return the platform rule (payout share, reporting regime, WHT notes). |
| `form_1099k_threshold` | Return the US Form 1099-K (gross, transactions) threshold for a tax year. |
| `deductions_list` | List deductible expense categories with typical deductibility + caveats. |
| `ip_risks_list` | List IP/contract cross-border risk checklist with mitigations. |
| `jurisdictions_list` | List all jurisdictions covered by tax_data. |
| `knowledge_brain_query` | Query the knowledge brain for citations matching keywords/jurisdictions; flag gaps. |
| `language_detect` | Detect whether the query is Vietnamese or English. |

Every tool's full input/output JSON schema is written to `assets/schemas/tool_.schema.json` by `scripts/generate_manifest.py`.

## 7. Quality gates & verdicts

**Universal gates U1–U6**: ≥3 cited sources (≥1 Tier 1–2); disclosure before the recommendation; tier labels on every source; language matches the request; the declared template; every claim traceable to a source or `[analyst judgment]`.

**Domain gates G1–G4**: residency/PE assessed; withholding & treaty relief mapped per source→resident pair; VAT/GST addressed per jurisdiction; disclaimer present.

Enforcement: apply each gate in order; on failure run the auto-fix; after 2 failed retries emit an explicit limitation notice and continue. Never silently pass a gate.

**Verdict contract** (exactly one per run): `Compliant Plan` / `Conditional (documentation)` / `Compliance Risk` / `Inconclusive`.

## 8. Hooks & lifecycle

`agent.hooks.HookManager` dispatches lifecycle phases to every registered `Hook` (isolating failures). Built-in hooks: `LoggingHook` (error + run summary), `StateMetricsHook` (per-step metrics). `EventEmitter` records structured `Event`s on `RunState` and forwards them to hooks. Phases: `on_start`, `on_step_pre`, `on_step_post`, `on_gate`, `on_event`, `on_error`, `on_complete`.

## 9. Configuration & feature flags

Type-safe configuration lives in `config/` (`config/settings.py` + `config/default.toml`). Precedence: compiled defaults  `SKILL.md` is regenerated from the live registry; edit the registry (`agent/skills/*`) and re-run the generator rather than hand-editing the tables below this line.

## Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

- **Author:** [dungnotnull](https://github.com/dungnotnull)
- **Source:** [dungnotnull/cross-border-streamer-tax-legal-advisor-agent-skill](https://github.com/dungnotnull/cross-border-streamer-tax-legal-advisor-agent-skill)
- **License:** MIT

Install and usage instructions live in the source repository linked above.

## Pricing

- **Free** — Free

## Security capabilities

Automated source analysis of v0.1.0 — what this tool can access:

- **Network access:** no
- **Filesystem access:** no
- **Shell / process execution:** no
- **Environment & secrets:** no
- **Dynamic code execution:** no

*"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.*


## Versions

- **0.1.0** — security scan: passed — Imported from the upstream source.

## Links

- Listing page: https://agentstack.voostack.com/l/skill-dungnotnull-cross-border-streamer-tax-legal-advisor-agent-skill-cross-border-streamer-tax-legal-advisor-agent-skill
- Seller: https://agentstack.voostack.com/s/dungnotnull
- Browse the marketplace: https://agentstack.voostack.com/browse

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