web-deep-search

name	web-deep-search
description	Deep web research via WebSearch + WebFetch. Modes: search, reason, research. Use for facts or cited reports.

Multi-source web research with three depth levels using Claude Code's built-in `WebSearch` and `WebFetch` tools. Use for fact-checking, technology comparisons, and current information beyond training data.

<when_to_activate>

• Need current information beyond training data
• Technology comparison or evaluation
• Library/framework version-specific questions
• Market research or industry analysis
• Fact-checking before making architectural decisions </when_to_activate>

<prior_session_input> When the user references a prior session, transcript, or "previous research," READ IT FIRST before doing fresh searches. Extract concrete artifacts (predictions, findings, decisions) and use them as inputs — do not redo the work from scratch. Path is usually under ~/.claude/projects/<project>/ as a .jsonl file. Check the subagents/ subdir too. (from session feedback: "did you use the context and preview session that i gave you to compare?") </prior_session_input>

Mode	Approach	Best For
search (default)	1–2 WebSearch calls, summarize titles/snippets	Quick facts, current events, quick lookups
reason	2–4 WebSearch calls + WebFetch top results, cross-reference	Comparisons, problem-solving, multi-source analysis
research	Fan-out searches (different angles) + fetch primary sources + adversarial verification	In-depth reports, market analysis, literature reviews

Rule: Default to search. Escalate to reason when sources disagree. Reserve research for exhaustive analysis with citations.

search mode

1. One targeted WebSearch query.
2. If results sufficient, synthesize answer with source URLs.
3. If insufficient, run one refined query.

reason mode

1. Run 2–4 WebSearch queries from different angles (technical docs, comparison articles, recent posts).
2. WebFetch the top 2–3 most authoritative URLs.
3. Cross-reference claims; flag disagreements between sources.
4. Synthesize with inline citations: [per docs.example.com].

research mode

1. Decompose question into 4–6 sub-questions.
2. WebSearch each sub-question in parallel.
3. WebFetch primary sources (official docs, vendor announcements, peer-reviewed where applicable).
4. Adversarially verify key claims (search for counter-evidence).
5. Produce structured report: findings, evidence, contradictions, citations.
6. For very deep research, prefer the deep-research slash command which orchestrates a multi-agent harness.

research mode (calibration variant)

When the task is a forecast and prior predictions exist:

1. Extract prior predictions (match-by-match if possible).
2. Score each against the actual outcome: exact / right-result-wrong-score / wrong.
3. Identify systematic biases (e.g. "underestimates blowouts", "over-rates favorites").
4. Re-predict future events with the bias correction explicitly applied. Skip step 4's reasoning if the user only wants the delta. (from session feedback: "guss vs actuall -> apply on the future possible?")

<source_quality> Prefer in this order:

1. Primary sources — official docs, RFCs, vendor announcements, source code
2. Authoritative secondary — well-maintained tech blogs, recognized publications
3. Aggregators — Stack Overflow, Reddit (only when corroborated)

Reject: SEO-spam content farms, AI-generated listicles, undated tutorials.

For version-specific questions, always verify the date — favor results from the last 12 months. </source_quality>

<recency_filter> WebSearch accepts no built-in recency flag, so add temporal hints to the query itself:

• "FastAPI 2026 release notes"
• "Python 3.13 features site:python.org"
• "latest <topic> changelog 2026" </recency_filter>

<error_handling>

Issue	Solution
Conflicting sources	Cite both, flag disagreement, prefer primary source
No relevant results	Refine query (more specific terms, add domain filter)
Stale information	Add year to query, prefer official changelogs/release notes
Paywall on key source	Search for the same content on the publisher's preview, or accept the limitation and cite the abstract
WebFetch returns empty body or "unable to fetch"	Fall back to the Playwright MCP plugin: browser_navigate then browser_evaluate to extract the rendered DOM. Common for FIFA.com, BBC, JS-heavy SPAs. (from session feedback: "use playwrute mcp plugine if wesearch does not work")
</error_handling>

<success_criteria>

• Mode matches query depth (don't fan out for a fact lookup)
• Every non-trivial claim has a source URL
• Conflicts between sources are surfaced, not hidden
• Primary sources preferred over aggregators
• No hallucinated facts — if the web didn't say it, don't claim it </success_criteria>