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

# Capability Contract Error • AI Agent SDK

> CapabilityContractError: A declared ``supports_*`` capability has no backing implementation.

# CapabilityContractError

> Defined in the [**base**](../modules/base) module.

<Badge color="blue">AI Agent</Badge>

A declared `supports_*` capability has no backing implementation.

Raised once, early — when an adapter is built/registered — so a
declared-but-unbacked capability can never reach a live turn as a lazy
`NotImplementedError` buried in the delivery loop. The message names the
offending flag and the method that must be overridden to back it.

## Source

<Card title="View on GitHub" icon="github" href="https://github.com/MervinPraison/PraisonAI/blob/main/src/praisonai-agents/praisonaiagents/bots/base.py#L74">
  `praisonaiagents/bots/base.py` at line 74
</Card>