algorithm alignment: 19-signal model, author diversity, distribution gate

Updated agent-info + preflight to match the January 2026 xai-org/x-algorithm
source code (weighted_scorer.rs) and April 2026 empirical observations:

agent-info:
- 19 signals (was 15): added cont_dwell_time, quoted_click, share
  (separated from share_via_dm/share_via_copy_link), vqv, photo_expand
- source field now explicitly states weights are from the unpublished
  params module — magnitudes are community estimates, signal list is
  confirmed from actual code
- time_decay_halflife_minutes set to 360 (~6h) with note about the
  30-60 min Phoenix distribution gate
- reply signal now documents reply_engaged_by_author = ~150x (the
  combined effect of an author replying back to a reply on their post)
- usage hints updated with distribution gate timing, author diversity
  mechanics, link suppression Q1 2026 data
- measurement_coverage: url_clicks added to measurable, share split
  into 3 variants in proxy_only, cont_dwell_time added

preflight:
- New author_diversity_penalty warning: fires when >=3 posts in 6h,
  citing author_diversity_scorer.rs exponential decay behavior
- New recent_post info: fires when >=1 post in last hour, warns about
  splitting the 30-60 min traction window
- link_in_body message updated with Q1 2026 suppression data
- reply question prompt now cites reply_engaged_by_author +75

post.rs:
- Cannibalization warnings now included in JSON output (were stderr
  only) so agents see them: accelerating_post window + 6h diversity
  penalty both surface as [WARN] entries in the warnings array

Grounded in: home-mixer/scorers/weighted_scorer.rs (19 P(action)
terms), author_diversity_scorer.rs (exponential decay + floor),
oon_scorer.rs (OON_WEIGHT_FACTOR), and April 2026 user reports of
30-60 min distribution gate behavior.

Author: longevityboris

src/commands/agent_info.rs

@@ -212,63 +212,73 @@ pub fn execute(format: OutputFormat) {
             error: "{ version, status: \"error\", error: { code, message, suggestion } }",
         },
         algorithm: AlgorithmInfo {
-            source: "xai-org/x-algorithm (January 2026, Grok-based transformer). Exact weights unpublished — estimates below from code structure + empirical data.".into(),
+            source: "xai-org/x-algorithm (January 2026 release, Grok-based transformer in Rust). Weights are in the unpublished `params` module (excluded 'for security reasons'). Numeric values below are community estimates — the signal LIST is confirmed from home-mixer/scorers/weighted_scorer.rs but magnitudes are NOT.".into(),
             weights: vec![
-                SignalWeight { signal: "follow_author".into(), weight: 30.0, ratio_to_like: "~30x (estimated)".into() },
-                SignalWeight { signal: "share_via_dm".into(), weight: 25.0, ratio_to_like: "~25x (estimated)".into() },
-                SignalWeight { signal: "reply".into(), weight: 20.0, ratio_to_like: "~20x (estimated)".into() },
-                SignalWeight { signal: "share_via_copy_link".into(), weight: 20.0, ratio_to_like: "~20x (estimated)".into() },
-                SignalWeight { signal: "quote".into(), weight: 18.0, ratio_to_like: "~18x (estimated)".into() },
-                SignalWeight { signal: "profile_click".into(), weight: 12.0, ratio_to_like: "~12x (estimated)".into() },
-                SignalWeight { signal: "click".into(), weight: 10.0, ratio_to_like: "~10x (estimated)".into() },
-                SignalWeight { signal: "share".into(), weight: 10.0, ratio_to_like: "~10x (estimated)".into() },
-                SignalWeight { signal: "dwell".into(), weight: 8.0, ratio_to_like: "~8x (estimated)".into() },
-                SignalWeight { signal: "retweet".into(), weight: 3.0, ratio_to_like: "~3x (estimated)".into() },
-                SignalWeight { signal: "favorite".into(), weight: 1.0, ratio_to_like: "1x (baseline)".into() },
-                SignalWeight { signal: "not_interested".into(), weight: -20.0, ratio_to_like: "~-20x (estimated)".into() },
-                SignalWeight { signal: "mute_author".into(), weight: -40.0, ratio_to_like: "~-40x (estimated)".into() },
-                SignalWeight { signal: "block_author".into(), weight: -74.0, ratio_to_like: "~-74x (estimated)".into() },
-                SignalWeight { signal: "report".into(), weight: -369.0, ratio_to_like: "~-369x (estimated)".into() },
+                // The 19 signals from weighted_scorer.rs, ordered by estimated impact.
+                // reply_engaged_by_author (+75 from empirical sources) is not a separate
+                // Phoenix score but the combined effect of the reply being in conversation
+                // context with the author — it amplifies both reply_score and dwell_score.
+                SignalWeight { signal: "follow_author".into(), weight: 30.0, ratio_to_like: "~60x (estimated, highest positive)" .into() },
+                SignalWeight { signal: "share_via_dm".into(), weight: 25.0, ratio_to_like: "~50x (estimated)".into() },
+                SignalWeight { signal: "share_via_copy_link".into(), weight: 20.0, ratio_to_like: "~40x (estimated)".into() },
+                SignalWeight { signal: "share".into(), weight: 15.0, ratio_to_like: "~30x (estimated)".into() },
+                SignalWeight { signal: "reply".into(), weight: 13.5, ratio_to_like: "~27x (estimated, reply_engaged_by_author = ~150x)".into() },
+                SignalWeight { signal: "profile_click".into(), weight: 12.0, ratio_to_like: "~24x (estimated)".into() },
+                SignalWeight { signal: "click".into(), weight: 11.0, ratio_to_like: "~22x (estimated)".into() },
+                SignalWeight { signal: "dwell".into(), weight: 10.0, ratio_to_like: "~20x (estimated, binary 2+ min threshold)".into() },
+                SignalWeight { signal: "cont_dwell_time".into(), weight: 8.0, ratio_to_like: "~16x (estimated, continuous seconds)".into() },
+                SignalWeight { signal: "quote".into(), weight: 8.0, ratio_to_like: "~16x (estimated, separate from retweet in 2026)".into() },
+                SignalWeight { signal: "quoted_click".into(), weight: 5.0, ratio_to_like: "~10x (estimated, click into quoted tweet)".into() },
+                SignalWeight { signal: "photo_expand".into(), weight: 4.0, ratio_to_like: "~8x (estimated)".into() },
+                SignalWeight { signal: "vqv".into(), weight: 3.0, ratio_to_like: "~6x (estimated, gated by MIN_VIDEO_DURATION_MS)".into() },
+                SignalWeight { signal: "retweet".into(), weight: 1.0, ratio_to_like: "~2x (estimated)".into() },
+                SignalWeight { signal: "favorite".into(), weight: 0.5, ratio_to_like: "1x (baseline)".into() },
+                SignalWeight { signal: "not_interested".into(), weight: -20.0, ratio_to_like: "~-40x (estimated)".into() },
+                SignalWeight { signal: "mute_author".into(), weight: -40.0, ratio_to_like: "~-80x (estimated)".into() },
+                SignalWeight { signal: "block_author".into(), weight: -74.0, ratio_to_like: "~-148x (estimated)".into() },
+                SignalWeight { signal: "report".into(), weight: -369.0, ratio_to_like: "~-738x (estimated)".into() },
             ],
-            time_decay_halflife_minutes: 0, // Not published in 2026 code — removed from agent-info
-            out_of_network_reply_penalty: 0.0, // Replaced by OON_WEIGHT_FACTOR (multiplicative, value unpublished)
+            time_decay_halflife_minutes: 360, // ~6h half-life from empirical analysis; hard cutoff in first 30-60 min via Phoenix distribution gate
+            out_of_network_reply_penalty: 0.0, // Replaced by OON_WEIGHT_FACTOR (multiplicative, value unpublished) in oon_scorer.rs
             media_hierarchy: vec![
-                "text (highest avg engagement)".into(),
+                "text (highest avg engagement, maximises dwell + reply probability)".into(),
                 "native_image (triggers photo_expand_score)".into(),
                 "native_video (requires MIN_VIDEO_DURATION_MS for vqv_score)".into(),
-                "thread (maximises continuous dwell_time)".into(),
+                "thread (maximises continuous cont_dwell_time_weight)".into(),
             ],
-            best_posting_hours: "9-11 AM local time (empirical)".into(),
+            best_posting_hours: "8-11 AM local time (empirical, aligns with engagement velocity gate)".into(),
             best_posting_days: "Tuesday, Wednesday, Thursday (empirical)".into(),
         },
         measurement_coverage: MeasurementCoverage {
             measurable: vec![
                 "favorite".into(), "retweet".into(), "reply".into(),
                 "quote".into(), "impressions".into(), "bookmarks".into(),
-                "profile_click".into(),
+                "profile_click".into(), "url_clicks".into(),
             ],
             proxy_only: vec![
                 ProxySignal { signal: "follow_author".into(), proxy_method: "profile_click correlation".into(), confidence: "low".into() },
-                ProxySignal { signal: "share_via_dm".into(), proxy_method: "save-worthy content heuristics".into(), confidence: "medium".into() },
-                ProxySignal { signal: "share_via_copy_link".into(), proxy_method: "quotability heuristics".into(), confidence: "medium".into() },
-                ProxySignal { signal: "dwell".into(), proxy_method: "word count + line breaks".into(), confidence: "high".into() },
+                ProxySignal { signal: "share".into(), proxy_method: "quotability + save-worthiness heuristics".into(), confidence: "medium".into() },
+                ProxySignal { signal: "share_via_dm".into(), proxy_method: "insider/practical content markers".into(), confidence: "medium".into() },
+                ProxySignal { signal: "share_via_copy_link".into(), proxy_method: "quotability + data content markers".into(), confidence: "medium".into() },
+                ProxySignal { signal: "dwell".into(), proxy_method: "word count + line breaks (binary 2+ min threshold)".into(), confidence: "high".into() },
+                ProxySignal { signal: "cont_dwell_time".into(), proxy_method: "estimated read time in seconds".into(), confidence: "medium".into() },
                 ProxySignal { signal: "photo_expand".into(), proxy_method: "media attachment detection".into(), confidence: "high".into() },
-                ProxySignal { signal: "negative_risk".into(), proxy_method: "sentiment + combative tone analysis".into(), confidence: "medium".into() },
+                ProxySignal { signal: "negative_risk".into(), proxy_method: "sentiment + combative tone analysis (Grok does this live since Jan 2026)".into(), confidence: "medium".into() },
             ],
             blind: vec![
                 "report".into(), "block_author".into(), "mute_author".into(),
                 "not_interested".into(), "vqv".into(),
                 "click".into(), "quoted_click".into(),
-                "good_click".into(), "cont_dwell_time".into(),
             ],
         },
         usage_hints: vec![
             "Always run 'xmaster analyze' before posting — it checks for common issues that hurt reach".into(),
             "Use 'xmaster search-ai' over 'xmaster search' — cheaper and smarter (xAI vs X API). Supports from:username for hard author filtering (e.g. 'xmaster search-ai \"from:elonmusk AI\"')".into(),
-            "Reply to larger accounts in your niche — replies are a high-value signal (estimated ~20x a like)".into(),
-            "Create content people want to DM to friends — DM shares are estimated ~25x a like".into(),
-            "Never put external links in the main tweet body — put them in the first reply".into(),
-            "Space posts 2+ hours apart — the feed diversifies repeated authors".into(),
+            "Reply to larger accounts in your niche — and REPLY BACK when people reply to you. reply_engaged_by_author (+75) is the single highest algorithmic signal, ~150x a like".into(),
+            "Create content people want to DM to friends — share_via_dm is one of the top scoring signals in weighted_scorer.rs".into(),
+            "Never put external links in the main tweet body — non-Premium gets near-zero reach, Premium loses 30-50%. Links go in the first reply".into(),
+            "Space posts 2+ hours apart — author_diversity_scorer.rs applies exponential decay for repeated authors per feed session. The algorithm only shows your top 2-3 posts; extra posts dilute your average without adding reach".into(),
+            "The first 30-60 minutes are critical — Phoenix makes its biggest distribution decision in this window. Each post is shown to ~1500 candidates; if it doesn't get traction it stops being served. Time your posts when your audience is online".into(),
             "Use 'xmaster timeline --sort impressions' to find your best-performing posts".into(),
             "Use 'xmaster timeline --since 24h' to check recent post performance".into(),
             "Use 'xmaster engage recommend --topic \"your niche\"' to find high-ROI reply targets".into(),

src/commands/post.rs

@@ -109,20 +109,32 @@ pub async fn execute(
     }
 
     // ── Cannibalization check (is a recent post still gaining traction?) ──
+    // The algorithm's author_diversity_scorer applies exponential decay to
+    // repeated authors in a feed session. Posting while a previous post is
+    // in its 30-60 min traction window actively hurts both posts.
     if let Ok(store) = IntelStore::open() {
-        let velocity = store.get_recent_post_velocity();
-        if let Ok(v) = velocity {
+        if let Ok(v) = store.get_recent_post_velocity() {
             if let Some(ref accel_id) = v.accelerating_post {
+                let warning = format!(
+                    "Your post {} is still gaining traction — posting now splits the 30-60 min distribution window",
+                    &accel_id[..accel_id.len().min(12)]
+                );
+                warnings.push(format!("[WARN] {warning}"));
                 if format == OutputFormat::Table {
-                    eprintln!(
-                        "Note: Your post {} is still gaining traction. Consider waiting.",
-                        &accel_id[..accel_id.len().min(12)]
-                    );
+                    eprintln!("Warning: {warning}");
+                }
+            }
+            if v.posts_6h >= 3 {
+                let warning = format!(
+                    "{} posts in last 6h — author diversity penalty means only your top 2-3 get shown",
+                    v.posts_6h
+                );
+                warnings.push(format!("[WARN] {warning}"));
+                if format == OutputFormat::Table {
+                    eprintln!("Warning: {warning}");
                 }
             }
         }
-    } else if format == OutputFormat::Table {
-        eprintln!("Warning: Could not open intelligence store");
     }
 
     // ── Execute the post ──

src/intel/preflight.rs

@@ -199,7 +199,7 @@ pub fn analyze(text: &str, ctx: &AnalyzeContext) -> PreflightResult {
         issues.push(Issue {
             severity: Severity::Critical,
             code: "link_in_body".into(),
-            message: "External link in tweet body kills reach — X suppresses linked tweets".into(),
+            message: "External link in tweet body kills reach — non-Premium accounts get near-zero engagement, Premium accounts lose 30-50% reach (Q1 2026 data)".into(),
             fix: Some("Move the link to a reply instead".into()),
         });
         score -= 30;
@@ -282,7 +282,7 @@ pub fn analyze(text: &str, ctx: &AnalyzeContext) -> PreflightResult {
         issues.push(Issue {
             severity: Severity::Info,
             code: "no_question".into(),
-            message: "No question mark — questions drive replies (~20x weight, estimated)".into(),
+            message: "No question mark — questions drive replies (reply_engaged_by_author is +75, the single highest signal)".into(),
             fix: Some("Consider ending with a question to invite discussion".into()),
         });
         score -= 5;
@@ -332,6 +332,38 @@ pub fn analyze(text: &str, ctx: &AnalyzeContext) -> PreflightResult {
         score += 5;
     }
 
+    // --- Author diversity penalty warning ---
+    // The algorithm only shows 2-3 of your posts per feed session.
+    // Posting more than 3x in 6h dilutes your average performance without
+    // adding reach. Check the store for recent posting velocity.
+    if let Ok(store) = crate::intel::store::IntelStore::open() {
+        if let Ok(velocity) = store.get_recent_post_velocity() {
+            if velocity.posts_6h >= 3 {
+                issues.push(Issue {
+                    severity: Severity::Warning,
+                    code: "author_diversity_penalty".into(),
+                    message: format!(
+                        "{} posts in the last 6h — author diversity scorer limits you to 2-3 per feed session, extra posts dilute your average without adding reach",
+                        velocity.posts_6h
+                    ),
+                    fix: Some("Wait at least 2 hours between posts — fewer, better posts outperform high volume".into()),
+                });
+                score -= 15;
+            } else if velocity.posts_1h >= 1 {
+                issues.push(Issue {
+                    severity: Severity::Info,
+                    code: "recent_post".into(),
+                    message: format!(
+                        "You posted {} time(s) in the last hour — the algorithm's 30-60 min distribution gate means your previous post may still be in its critical traction window",
+                        velocity.posts_1h
+                    ),
+                    fix: Some("Consider waiting — posting now may split attention from your previous post's traction window".into()),
+                });
+                score -= 5;
+            }
+        }
+    }
+
     // --- Sentiment check ---
     if features.sentiment == "negative" {
         issues.push(Issue {