Context Engineering Templates

Template 1: Context packet

Use this when a human or orchestrator needs to hand Claude a bounded task with clear source boundaries.

<context_packet>
  <task>
    What Claude should accomplish in this run.
  </task>
  <success_criteria>
    Concrete checks for a good answer or completed action.
  </success_criteria>
  <allowed_actions>
    Tools, edits, commands, or decisions Claude may perform.
  </allowed_actions>
  <constraints>
    Hard boundaries, security rules, freshness requirements, and non-goals.
  </constraints>
  <sources>
    Source list with URLs, file paths, timestamps, and relevance notes.
  </sources>
</context_packet>

Template 2: Source packet

Use this when accuracy depends on verifiable evidence. The point is to separate source metadata from interpretation.

<source_packet generated_at="2026-07-06">
  <source id="S1">
    <title>Context windows</title>
    <publisher>Claude Platform Docs</publisher>
    <url>https://platform.claude.com/docs/en/build-with-claude/context-windows</url>
    <accessed>2026-07-06</accessed>
    <relevance>Defines context-window behavior and compaction guidance.</relevance>
    <notes>Use for current Claude context-window claims.</notes>
  </source>
</source_packet>

Template 3: Compaction handoff

Use this when a session is about to be compacted or handed to another agent. Preserve exact facts, unresolved risks, and next actions.

<compaction_handoff>
  <objective>Current goal and why it matters.</objective>
  <decisions>Decisions already made, with reasons.</decisions>
  <state>Files touched, commands run, source facts established.</state>
  <open_questions>Unknowns that still affect the outcome.</open_questions>
  <next_actions>Ordered, concrete next steps.</next_actions>
  <do_not_repeat>Explorations already ruled out.</do_not_repeat>
</compaction_handoff>

Template 4: MCP resource inventory

Use this before adding MCP resources to an agent. It makes resource priority, sensitivity, and freshness explicit.

resource: file:///repo/README.md
owner: engineering-docs
audience: assistant,user
priority: 0.8
lastModified: 2026-07-01T18:12:00Z
sensitivity: internal
load_strategy: summary-first
refresh_rule: check lastModified before use
failure_mode: if unavailable, ask for current docs rather than guessing

FAQ

Sources Used

• Prompting best practices, Claude Platform Docs. Accessed 2026-07-06. Official guidance on clear instructions, examples, XML sections, long-context prompting, and tool-use prompting.
• Token counting, Claude Platform Docs. Accessed 2026-07-06. Official endpoint guidance for estimating input tokens, costs, rate limits, and model routing.
• Context engineering: memory, compaction, and tool clearing, Claude Cookbook. Accessed 2026-07-06. Cookbook comparison of server-side compaction, context editing, tool-result clearing, and memory.
• Resources, Model Context Protocol Specification. Accessed 2026-07-06. Protocol definition for resources, resource templates, subscriptions, contents, and annotations.