> ## Documentation Index > Fetch the complete documentation index at: https://docs.cala.ai/llms.txt > Use this file to discover all available pages before exploring further. # Search > Search verified knowledge using natural language questions. Best for open-ended queries where you need explanations, context, and sources — not just entity lists. Returns markdown content with explainability, source citations, and matching entities. Examples: `{"input": "What are the biggest AI startups in Europe by funding?"}` `{"input": "Who founded Stripe and what is their background?"}` `{"input": "What regulations affect fintech companies in the EU?"}` Use this when: You need a researched, sourced answer to a question. Prefer `knowledge_query` for structured filtering, or `entity_search` if you just need to find an entity by name. ## OpenAPI ````yaml https://api.cala.ai/openapi.json post /v1/knowledge/search openapi: 3.1.0 info: title: Cala AI summary: Verified, reliable knowledge one API call away description: > ### Knowledge Search Let's you search for verified knowledge to empower your AI Agent with the **right context**. ### Knowledge Entities Get information about entities, **structured** and reliable. version: Beta 1.0 servers: - url: https://api.cala.ai/ security: [] paths: /v1/knowledge/search: post: tags: - API v1 - Knowledge summary: Search description: >- Search verified knowledge using natural language questions. Best for open-ended queries where you need explanations, context, and sources — not just entity lists. Returns markdown content with explainability, source citations, and matching entities. Examples: `{"input": "What are the biggest AI startups in Europe by funding?"}` `{"input": "Who founded Stripe and what is their background?"}` `{"input": "What regulations affect fintech companies in the EU?"}` Use this when: You need a researched, sourced answer to a question. Prefer `knowledge_query` for structured filtering, or `entity_search` if you just need to find an entity by name. operationId: knowledge_search requestBody: content: application/json: schema: $ref: '#/components/schemas/SearchRequest' required: true responses: '200': description: Successful Response content: application/json: schema: $ref: '#/components/schemas/Answer' '422': description: Validation Error content: application/json: schema: $ref: '#/components/schemas/HTTPValidationError' '429': description: Too many requests (rate limit exceeded) content: application/json: example: error: rate_limit_exceeded message: Rate limit exceeded. Too many requests. security: - APIKeyHeader: [] components: schemas: SearchRequest: properties: input: type: string title: Input examples: - >- What are the most promising climate tech startups in Southern Europe? explainability: type: boolean title: Explainability description: Whether to generate explainability for the answer. default: true examples: - true return_entities: type: boolean title: Return Entities description: Whether to return the entities identified in the answer. default: true examples: - true type: object required: - input title: SearchRequest example: input: What are the most promising climate tech startups in Southern Europe? Answer: properties: content: type: string title: Content description: A succinct answer to the user's input in Markdown format. examples: - >- **Altano Energy (Spain)** — Madrid-based, developing renewable energy projects across Spain. Altano secured €60M Series C in 2025 from M&G Investments and Pioneer Point Partners. explainability: anyOf: - items: $ref: '#/components/schemas/ReasoningSteps' type: array - type: 'null' title: Explainability description: A list of reasoning steps to get to that answer. context: items: $ref: '#/components/schemas/KnowBit' type: array title: Context description: A list of facts that support the answer. entities: anyOf: - items: $ref: '#/components/schemas/EntityMention' type: array - type: 'null' title: Entities description: Entities identified in the answer. type: object required: - content - explainability - context - entities title: Answer description: >- The answer to the user's input with the reasoning steps and the context that support the answer. example: content: >- **Altano Energy (Spain)** — Madrid-based, developing renewable energy projects across Spain. Altano secured €60M Series C in 2025 from M&G Investments and Pioneer Point Partners. context: - content: >- Altano Energy - €60m (Series C, Jul 2025). Develops and operates renewable energy projects across Spain... id: 732e1954-9538-4fbc-a565-db2f8c07ad4e entities: - entity_type: Company id: 0abe9580-5abb-46df-9506-5dc784520b69 mentions: - Altano Energy - Altano name: Altano Energy explainability: - content: >- Altano Energy secured a €60 million Series C round in July 2025 from Pioneer Point Partners and M&G Investments. references: - f22a1a96-6234-48d7-95c2-8b049f00fdab HTTPValidationError: properties: detail: items: $ref: '#/components/schemas/ValidationError' type: array title: Detail type: object title: HTTPValidationError ReasoningSteps: properties: content: type: string title: Content description: The content of the reasoning step. examples: - >- Altano Energy secured a €60 million Series C round in July 2025 from Pioneer Point Partners and M&G Investments. references: items: type: string format: uuid type: array title: References description: >- The UUIDs of the KnowBits referenced in the reasoning step. Must match 'id' fields in context array. examples: - - f22a1a96-6234-48d7-95c2-8b049f00fdab type: object required: - content - references title: ReasoningSteps description: A step in the reasoning process. KnowBit: properties: id: type: string format: uuid title: Id description: The id of the KnowBit. examples: - 732e1954-9538-4fbc-a565-db2f8c07ad4e content: type: string title: Content description: The information contained in the KnowBit. examples: - >- Altano Energy - €60m (Series C, Jul 2025). Develops and operates renewable energy projects across Spain... origins: items: $ref: '#/components/schemas/Origin' type: array title: Origins description: The origins from which the KnowBit was extracted. type: object required: - id - content - origins title: KnowBit description: >- A KnowBit is like a fact, a piece of information that supports the answer. EntityMention: properties: id: type: string format: uuid title: Id description: The ID of the entity examples: - 0abe9580-5abb-46df-9506-5dc784520b69 name: type: string title: Name description: The name of the entity examples: - Altano Energy entity_type: type: string enum: - Entity - Animal - Award - Organization - Company - EducationalInstitution - Person - Event - GPE - Country - CountryRegion - Industry - FinancialMetric - Group - CorporateEvent - PrivateCompanyFundingRound - Facility - Location - Organism - Plant - Product - Sanction - WorkOfArt - Law - Language - Exchange - Future - Commodity - PositioningMetric - MacroIndicatorPublication - MacroIndicator title: Entity Type description: The type of the entity examples: - Company mentions: items: type: string type: array title: Mentions description: Mentions of this entity in the response. examples: - - Altano Energy - Altano type: object required: - id - name - entity_type - mentions title: EntityMention ValidationError: properties: loc: items: anyOf: - type: string - type: integer type: array title: Location msg: type: string title: Message type: type: string title: Error Type type: object required: - loc - msg - type title: ValidationError Origin: properties: source: $ref: '#/components/schemas/Source' document: $ref: '#/components/schemas/Document' breadcrumb: items: type: string type: array title: Breadcrumb description: Breadcrumb field (always empty for compatibility) examples: - - '' type: object required: - source - document - breadcrumb title: Origin description: The sources and documents from which the KnowBit was extracted. Source: properties: name: type: string title: Name description: The name or title of the source. examples: - Impact Loop url: type: string minLength: 1 format: uri title: URL description: The URL of the source. examples: - https://www.impactloop.com/ type: object required: - name - url title: Source description: >- Organization that provides, creates, or publishes the document, like a web site, a book, a report, etc. Document: properties: name: type: string title: Name description: The name or title of the document. examples: - Europe's top 25 climate tech funding rounds this year url: type: string minLength: 1 format: uri title: URL description: The URL of the document. examples: - >- https://www.impactloop.com/artikel/europe-s-25-largest-climate-tech-fundraises-funding-2025-and-the-investors-behind-them type: object required: - name - url title: Document description: Specific text, report, article, or file that contains the information. securitySchemes: APIKeyHeader: type: apiKey in: header name: X-API-KEY ````