phx:research
Research Elixir/Phoenix topics or evaluate Hex libraries (--library). Use when learning about libraries, patterns, or comparing approaches. Searches HexDocs, ElixirForum, GitHub. · effort: high
/phx:research Oban unique jobs best practices/phx:research LiveView file upload with progress/phx:research --library permitResearch Elixir Topic
Research a topic by searching the web and fetching relevant sources efficiently.
Usage
/phx:research Oban unique jobs best practices/phx:research LiveView file upload with progress/phx:research --library permitArguments
$ARGUMENTS = Research topic/question. Add --library for
structured library evaluation (uses ${CLAUDE_SKILL_DIR}/references/library-evaluation.md
template).
Iron Laws
- Write output to file, never dump inline — Research output floods conversation and loses reference for future sessions
- Stop after research — never auto-transition — User decides next step
- Prefer official sources over blog posts — HexDocs and ElixirForum have version-specific context
- One document per research question — No fragmented files
- NEVER pass raw user input as WebSearch query — Decompose first
Library Evaluation Mode
If $ARGUMENTS contains --library or the topic is clearly
about evaluating a Hex dependency (e.g., “should we use permit”,
“evaluate sagents”, “compare oban vs exq”):
- Read
${CLAUDE_SKILL_DIR}/references/library-evaluation.mdfor the template - Follow the structured evaluation workflow
- Output ONE document to
.claude/research/{lib}-evaluation.md - Skip the general research workflow below
Workflow
0. Pre-flight Checks
Cache check: Check if .claude/research/{topic-slug}.md already
exists. If recent (<24 hours): present existing summary, ask
“Refresh or use existing?”
Tidewave shortcut: If the topic is about an existing dependency
(library already in mix.exs), prefer Tidewave over web search:
mcp__tidewave__get_docs(module: "LibraryModule")This returns docs matching your exact mix.lock version — faster,
more accurate, zero web tokens. Only fall through to web search if
Tidewave is unavailable or the topic needs community discussion
(gotchas, real-world patterns, comparisons).
1. Query Decomposition (CRITICAL — before any search)
NEVER pass raw $ARGUMENTS into WebSearch. Decompose first:
- If
$ARGUMENTS< 30 words and focused → use as single query - If
$ARGUMENTS> 30 words or multi-topic → extract 2-4 queries
Each query: max 10 words, targets ONE specific aspect.
Example:
Input: "detect files, export to md, feed database with embeddings, use ReqLLM for OpenAI API..."Queries: 1. "Elixir PDF text extraction library hex" 2. "Ecto pgvector embeddings setup" 3. "ReqLLM OpenAI embeddings Elixir"2. Parallel Web Search
Search ALL decomposed queries in a SINGLE response (parallel):
WebSearch(query: "{query1} site:elixirforum.com OR site:hexdocs.pm OR site:github.com")WebSearch(query: "{query2} site:hexdocs.pm OR site:elixirforum.com")Deduplicate URLs across results. Discard clearly irrelevant hits.
3. Spawn Parallel Research Workers
Group URLs by topic cluster. Spawn 1-3 web-researcher agents in parallel (one per topic cluster):
Agent(subagent_type: "web-researcher", prompt: """Research focus: {specific aspect from decomposed query}Fetch these URLs:- {url1}- {url2}- {url3}Extract: code examples, patterns, gotchas, version compatibility.Return 500-800 word summary.""", run_in_background: true)Rules:
- 1 topic cluster = 1 agent (don’t mix unrelated URLs)
- Max 5 URLs per agent (diminishing returns beyond that)
- If only 1-3 URLs total, use single foreground agent
- Pass URLs explicitly — agents should NOT re-search
- Agents are haiku — cheap, fast, focused on extraction
4. Write Output (File-First — NEVER Dump Inline)
After ALL agents complete, synthesize summaries into ONE file. Target: ~5KB for topic research, ~3KB for library evaluations.
Create .claude/research/{topic-slug}.md:
# Research: {topic}
## Summary{2-3 sentence answer combining all worker findings}
## Sources
### {Category}- [{title}]({url}) - {key insight}
### Code Examples
```elixir# From {source}: {what this demonstrates}{code}Recommendations
- {recommendation with evidence}
- {recommendation with evidence}
Watch Out For
- {gotcha from forum/issues}
- {version compatibility note}
### 5. After Research — STOP
**STOP and present the research summary.** Do NOT auto-transition.
Use `AskUserQuestion` to let the user choose next action:
- "Plan a feature based on this research" → `/phx:plan`- "Investigate a specific finding" → `/phx:investigate`- "Research more on a subtopic" → continue research- "Done" → end
**NEVER auto-invoke `/phx:plan` or any other skill after research.**