> ## Documentation Index
> Fetch the complete documentation index at: https://docs.erstan.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Partner Content Model

> How Erstan separates tools, skills, agents, templates, and packs.

Erstan content is split into deterministic operations and reusable guidance. Use the narrowest object that fits the job.

## Layers

| Layer     | Definition                                                         | Use it when                                                       |
| --------- | ------------------------------------------------------------------ | ----------------------------------------------------------------- |
| Connector | A connection to an external system, such as NetSuite.              | The user needs authenticated access to outside data or actions.   |
| Tool      | A deterministic, parameterized operation.                          | You would write an automated test asserting the output.           |
| Skill     | Reusable instructions, reference files, and optional actions.      | You would review the output like a colleague's work.              |
| Agent     | The identity and composition that performs work.                   | The product question is who is doing the work.                    |
| Template  | A copyable starting point for a skill, agent, prompt, or workflow. | The user should copy it and edit it.                              |
| Pack      | A curated bundle of templates and setup defaults.                  | Installation should provision a complete role or workflow family. |

## Decision Tests

* Tool: you would write an automated test asserting its output.
* Skill: you would review its output like a colleague's work.
* Agent: who is doing the work.
* Template: you copy and edit it.

Deterministic operations are tools. Behavioral guidance is a skill. Identity and composition are agents. Anything intended to be copied and edited is a template.

## Skill Tiers

| Tier         | Owner             | Governance                                                            |
| ------------ | ----------------- | --------------------------------------------------------------------- |
| T0 Platform  | Erstan            | Always available guardrails and platform capabilities.                |
| T1 Built-in  | Erstan            | Built into the runtime and paired only with Runtime Baseline tools.   |
| T2 Curated   | Erstan or partner | Installed from the library or marketplace, versioned, and reviewable. |
| T3 Workspace | Customer          | Authored or forked inside a workspace.                                |

T1 built-in skills may reference only Runtime Baseline tools. Broader or domain-specific tool use belongs in T2 curated skills and agents.

## Tool Prefixes

* `er_` tools are Erstan-native deterministic operations.
* `ns_` tools are NetSuite MCP core tools.
* `er_ns_` tools are Erstan SuiteApp custom NetSuite MCP tools.
* `er_suiteql_example_find`, `er_suiteql_query_validate`, and `er_suiteql_query_fix` are Erstan-native SuiteQL helpers. Their former `ns_` names are accepted only as backward-compatible runtime aliases.

## Worked Example

Use `er_file_load` to read or OCR a file. Use the File Understanding skill when the task needs interpretation, classification, comparison, or schema-shaped extraction after loading the file.

The tool gives the model reliable bytes and text. The skill teaches when and how to reason over that material.