Summarizer

Read the fidelity rules and execution contract. They govern all routes below.

Resolve the request

Identify the requested operation (summary, synthesis, comparison or relay), source scope, format and any explicit length/focus requirement. Preserve user-provided directory scope; do not silently replace a directory with one file. Enumerate readable sources and report omissions. Do not turn a summary request into implementation, external research or code execution without authorization.

Select and read one template:

Signal	Format	Template
No format specified; full/detailed summary	structured	structured
Bullet points, key points	bullets	bullets
TL;DR, one-liner, nutshell	tldr	TL;DR
JSON, machine-readable data	json	JSON
Table, tabular, grid	table	table
Outline, hierarchy, table of contents	outline	outline

The selected format overrides legacy structured-only requirements in source skills. In particular, raw JSON has no Markdown envelope and TL;DR has no mandatory What Was NOT Found section.

Route sources

Resolve cardinality first, then transport (local, URL, inline) and actual media type. A local image is not ordinary text just because it has a file path; a URL can return an image or PDF. Inspect content/type evidence rather than relying solely on extensions.

Input	Method
Text/code/config/data/document file	file-summarization
URL	url-summarization; route acquired visual content to the image method
Image or screenshot	image-summarization
Inline text	Extract passages directly, then apply fidelity and the selected template
Multiple sources	Apply the appropriate method to each; synthesize only when requested
Existing agent result	agent-result-relay

For requested integration, load multi-source-synthesis. Otherwise keep individual summaries separately attributable. Record failed sources alongside the successful ones rather than dropping them from the input set.

Delegate when useful

Use summarizer:file-summarizer, summarizer:url-summarizer, or summarizer:image-summarizer for an autonomous task when the host supports delegation. For an interactive conversation, or when agents are unavailable, run the same source skill directly.

Forward the format, source scope, focus, assigned output path and caller return contract. Supply the exact initial-task controls defined in the execution contract. Workers read their own skills and sources. Preserve context isolation instead of assuming parent-loaded instructions carry over.

For multiple independent sources, choose parallel extraction only when available capacity and source cost justify it. Use sequential execution when sources depend on earlier results. Interactive teams are appropriate only when workers need communication, not simply because there are three sources. If teams are used, collect explicit terminal results, retain each source's provenance, perform the full synthesis step and release workers. Worker agreement is not independent verification.

Deliver

Check support and coverage, render the selected template, then validate the final delivered result under the execution contract. A worker's validation does not cover a later rewritten synthesis. Preserve caller status envelopes separately from summary artifacts. Relay exact counts and failure reasons, name full result artifacts, and keep unverified behavior explicit.