Exa Search

Exa Search

Summary

Unlike keyword-based search, Exa understands context and retrieves high-quality, relevant results for technical research.

Domain: research

Skill Identity

Purpose

Semantic search using Exa API for security research queries. Unlike keyword-based search, Exa understands context and retrieves high-quality, relevant results for technical research.

Core Capabilities

1. Semantic Search: Context-aware query understanding
2. Date Filtering: Recent content prioritization
3. Domain Filtering: Target specific sources
4. Content Extraction: Full-text retrieval

Use Cases

• CVE Research: "Recent CVEs affecting Spring Boot applications"
• Exploit Techniques: "SSRF bypass techniques in AWS metadata service"
• Tool Research: "Best tools for JWT security testing"
• Threat Intelligence: "APT campaigns targeting healthcare 2024"

Exa API Reference

• Endpoint: https://api.exa.ai/search
• Auth: API key via X-API-Key header
• Docs: https://docs.exa.ai/

Query Strategy

• Semantic phrasing: Frame queries as full sentences ("How does X bypass Y?") rather than keyword strings; Exa's embedding model rewards natural-language intent.
• Iterative narrowing: Start broad, then re-query with terms surfaced by the first batch to drill into specifics.
• Source class filters: Restrict to includeDomains (e.g., ["github.com","arxiv.org"]) for code/research, or excludeDomains for noisy aggregators.
• Recency bias: Use startPublishedDate to suppress stale CVE write-ups when chasing live threats.

Result Triage

1. Reject low-authority hosts (link farms, scraped mirrors) by domain reputation.
2. Cross-reference at least two independent sources before treating a claim as fact.
3. Extract canonical artifacts (CVE IDs, commit hashes, IoCs) into structured notes for knowledge-ops.
4. Flag contradictory findings and escalate to deep-research instead of silently discarding.

Rate Limits & Cost Control

• Exa enforces per-minute and per-day quotas — batch related queries and cache responses by query hash.
• Prefer numResults: 10-20 per call; pagination is cheaper than re-querying.
• Use useAutoprompt: false once you have a polished query to avoid silent rewrites that inflate cost.
• Stream large content extractions instead of getContents on a long URL list.

Common Pitfalls

• Treating Exa as a keyword engine — short keyword queries underperform; semantic models need context.
• Skipping verification — semantic results can hallucinate relevance; always sanity-check top hits.
• Date drift — without startPublishedDate, archive copies of old CVE posts can outrank current advisories.
• Domain blindness — failing to include vendor-specific domains misses authoritative primary sources.

Advanced Query Patterns

• Boolean composition: Combine semantic queries with includeText / excludeText filters for precision targeting.
• Category targeting: Use category: "research paper" or category: "github" to narrow the search space before applying semantic filters.
• Proximity search: Embed technical terms in natural context ("zero-day exploit chain exploiting deserialization in Java") rather than listing keywords.
• Multi-hop retrieval: Use first-pass results to identify key authors, then search for their other publications with author: "name".

Content Extraction Workflow

1. Run initial search with numResults: 10 to identify the most relevant documents.
2. For top 3-5 hits, call getContents with text: true to retrieve full-text content.
3. Parse extracted text for canonical identifiers (CVE IDs, commit hashes, CWE numbers, CVSS scores).
4. Store structured extractions in knowledge-ops with source URL, extraction date, and confidence score.
5. For ambiguous or contradictory results, cross-reference with a second query using different phrasing.

Integration with Research Pipelines

• OSINT correlation: Feed Exa results into osint skill for cross-validation against multiple intelligence sources.
• Deep-research handoff: When Exa surfaces a complex topic, escalate to deep-research for systematic multi-source analysis.
• Chronicle logging: Archive search queries and results in chronicle for future reference and trend analysis.
• Article writing: Structure Exa findings into report-ready sections using article-writing templates.

Monitoring and Automation

• Set up recurring queries for high-priority topics (e.g., new CVEs for monitored products) with date-filtered searches.
• Track result count changes over time to detect surges in publication activity around specific vulnerabilities.
• Automate source discovery: periodically search for new security blogs and research outlets to expand coverage.
• Log all API calls (query, timestamp, result count, cost) for budget tracking and query optimization.

Quality Assurance

• Validate each result against the original query intent — semantic search can return topically adjacent but irrelevant results.
• Track precision@k (fraction of top-k results that are relevant) across query types to identify systematic weaknesses.
• Maintain a golden dataset of known-good queries and expected results for regression testing after API changes.
• Audit cost-per-actionable-finding to optimize query strategies over time.

Detection Methods

API Usage Patterns

• Anomalous query volume: Single token consuming >10x typical rate.
• Cross-domain correlation: Aggregating data from many domains (OSINT pattern).
• Off-hours bulk queries: Large query bursts outside business hours.

SIEM Detection Rules

• Splunk SPL: index=api gateway.route="/search" | stats count by api_key | sort -count | head 20
• Custom API gateway logs: Alert on anomalous query patterns.

Defense Evasion Techniques

Stealth Search

• Distribute across accounts: Use multiple API keys; below per-key rate limits.
• Slow & methodical: Pace queries below anomaly threshold.
• Cache results: Avoid re-querying same data.
• Mimic legitimate usage: Use natural language queries matching typical analyst patterns.

Integration

• Use after deep-research when primary sources are insufficient
• Feed results to knowledge-ops
• Complement social-intelligence for broader coverage