rho-coding-agent 1.16.0

A lightweight agent harness inspired by Pi
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163

//! Human-readable compaction tool-block display lines.
//!
//! Compaction is shown like a tool call: a running block while work is in
//! flight, then a finished block with the outcome facts we actually have.

use rho_sdk::ToolCallId;

use super::usage_cost::{format_token_count, format_usd};

/// Stable synthetic call id so live compaction can occupy the tool-call batch.
pub(super) fn compaction_call_id() -> ToolCallId {
    ToolCallId::from_string("rho:compact").expect("static compaction call id")
}

/// Facts available after compaction completes. All fields come from
/// [`rho_sdk::CompactionOutcome`] so the layout stays provider-neutral.
#[derive(Clone, Copy, Debug, PartialEq, Eq)]
pub(super) struct CompactionDisplayFacts {
    pub(super) previous_messages: usize,
    pub(super) current_messages: usize,
    pub(super) previous_tokens: u64,
    pub(super) current_tokens: u64,
    pub(super) cost_usd_micros: Option<u64>,
}

impl CompactionDisplayFacts {
    pub(super) fn from_outcome(outcome: &rho_sdk::CompactionOutcome) -> Self {
        Self {
            previous_messages: outcome.previous_messages(),
            current_messages: outcome.current_messages(),
            previous_tokens: outcome.previous_tokens(),
            current_tokens: outcome.current_tokens(),
            cost_usd_micros: outcome.cost_usd_micros(),
        }
    }

    pub(super) fn removed_tokens(self) -> u64 {
        self.previous_tokens.saturating_sub(self.current_tokens)
    }

    pub(super) fn removed_messages(self) -> usize {
        self.previous_messages.saturating_sub(self.current_messages)
    }

    pub(super) fn reduced(self) -> bool {
        self.removed_tokens() > 0 || self.removed_messages() > 0
    }
}

/// Terminal presentation state for a compaction tool block.
#[derive(Clone, Debug, PartialEq, Eq)]
pub(super) enum CompactionUiOutcome {
    Completed(CompactionDisplayFacts),
    Unchanged { detail: String },
    Failed { detail: String },
    Cancelled,
}

impl CompactionUiOutcome {
    pub(super) fn ok(&self) -> bool {
        !matches!(self, Self::Failed { .. })
    }

    pub(super) fn display_lines(&self) -> Vec<String> {
        match self {
            Self::Completed(facts) => completed_display_lines(*facts),
            Self::Unchanged { detail } => unchanged_display_lines(detail.clone()),
            Self::Failed { detail } => failed_display_lines(detail.clone()),
            Self::Cancelled => cancelled_display_lines(),
        }
    }
}

/// Running tool-block lines (layout A).
pub(super) fn running_display_lines() -> Vec<String> {
    vec!["compact".into(), "shrinking context…".into()]
}

/// Finished tool-block lines (layout 1), driven only by available facts.
pub(super) fn completed_display_lines(facts: CompactionDisplayFacts) -> Vec<String> {
    let mut lines = vec!["compact".into()];

    let has_token_signal = facts.previous_tokens > 0 || facts.current_tokens > 0;
    if has_token_signal {
        lines.push(token_summary_line(facts));
    }

    // Always show messages when tokens are missing, or when the message count
    // changed / both sides are non-zero so the reduction is legible.
    if !has_token_signal
        || facts.previous_messages != facts.current_messages
        || facts.previous_messages > 0
    {
        lines.push(message_summary_line(facts));
    }

    if let Some(cost) = facts.cost_usd_micros.filter(|cost| *cost > 0) {
        lines.push(format!("cost {}", format_usd(cost)));
    }

    if !facts.reduced() && lines.len() == 1 {
        lines.push("no reduction".into());
    }

    lines
}

/// Failed compact tool-block lines.
pub(super) fn failed_display_lines(detail: impl Into<String>) -> Vec<String> {
    vec!["compact".into(), "failed".into(), detail.into()]
}

/// Cancelled compact tool-block lines.
pub(super) fn cancelled_display_lines() -> Vec<String> {
    vec!["compact".into(), "cancelled".into()]
}

/// Unchanged / not-enough-history finished block.
pub(super) fn unchanged_display_lines(detail: impl Into<String>) -> Vec<String> {
    vec!["compact".into(), detail.into()]
}

fn token_summary_line(facts: CompactionDisplayFacts) -> String {
    let mut line = format!(
        "{} → {} tokens",
        format_token_count(facts.previous_tokens),
        format_token_count(facts.current_tokens),
    );
    let removed = facts.removed_tokens();
    if removed > 0 {
        let percent = reduction_percent(facts.previous_tokens, removed);
        line.push_str(&format!(
            "  (−{} · {percent}%)",
            format_token_count(removed)
        ));
    } else if facts.previous_tokens == facts.current_tokens && facts.previous_tokens > 0 {
        line.push_str("  (no change)");
    }
    line
}

fn message_summary_line(facts: CompactionDisplayFacts) -> String {
    let mut line = format!(
        "{} → {} messages",
        facts.previous_messages, facts.current_messages
    );
    let removed = facts.removed_messages();
    if removed > 0 {
        line.push_str(&format!("  (−{removed})"));
    }
    line
}

fn reduction_percent(previous: u64, removed: u64) -> u64 {
    if previous == 0 {
        return 0;
    }
    ((removed as f64 * 100.0) / previous as f64).round() as u64
}

#[cfg(test)]
#[path = "compaction_display_tests.rs"]
mod tests;