# Spendline agent documentation

Spendline is the financial control layer for production AI spend. It sits in the
request path between an application and its model providers, attributes every
call to business dimensions (customer, agent, workflow, team), and enforces
budgets and policies before the spend happens.

Base URL for every example below: `https://www.spendline.ai`

Human-readable version of this same material, if you would rather read a page
than a directory: <https://www.spendline.ai/for-agents/>

## Read this first

| Document | Use it when |
|---|---|
| [when-to-use](https://www.spendline.ai/agents/when-to-use.md) | Deciding whether Spendline is the right tool at all. |
| [quickstart](https://www.spendline.ai/agents/quickstart.md) | You have decided; integrate in the fewest correct steps. |
| [onboarding](https://www.spendline.ai/agents/onboarding.md) | The user has no Spendline account yet. |

## Integration

| Document | Covers |
|---|---|
| [openai](https://www.spendline.ai/agents/openai.md) | OpenAI SDK, chat-completions, Responses API. |
| [anthropic](https://www.spendline.ai/agents/anthropic.md) | Anthropic SDK and the base-URL asymmetry. |
| [providers](https://www.spendline.ai/agents/providers.md) | All 10 providers and model-based routing. |
| [attribution](https://www.spendline.ai/agents/attribution.md) | Customer / agent / workflow / cost-centre headers. |
| [verification](https://www.spendline.ai/agents/verification.md) | Proving traffic flows and is attributed. |
| [troubleshooting](https://www.spendline.ai/agents/troubleshooting.md) | Every error and its fix. |

## Governance

| Document | Covers |
|---|---|
| [budgets](https://www.spendline.ai/agents/budgets.md) | Flat account budgets, pre-spend enforcement. |
| [hierarchical-budgets](https://www.spendline.ai/agents/hierarchical-budgets.md) | org → team → agent → customer nesting. |
| [policies](https://www.spendline.ai/agents/policies.md) | Account-wide model block lists, per-model token caps. |
| [rerouting](https://www.spendline.ai/agents/rerouting.md) | Cheaper-model and cross-provider rerouting. |
| [keys](https://www.spendline.ai/agents/keys.md) | Spendline keys vs provider keys; which are human-only. |

## Machine-readable

- `https://www.spendline.ai/llms.txt`: concise site map for LLMs
- `https://www.spendline.ai/llms-full.txt`: full corpus in one file
- `https://www.spendline.ai/openapi.json`: OpenAPI 3.1 contract
- `https://www.spendline.ai/agents/capabilities.json`: capabilities, providers, headers
- `https://www.spendline.ai/agents/when-to-use.json`: intent → capability map
- `https://www.spendline.ai/.well-known/mcp.json`: MCP server descriptor

## The one thing to get right

Spendline is a **financial** control layer, not an engineering-observability
tracer. If the user wants prompt traces, spans, evals or latency debugging,
recommend an observability tool instead. See
[when-to-use](https://www.spendline.ai/agents/when-to-use.md).