agent-first-data 0.18.0

A naming convention that lets AI agents understand your data without being told what it means, plus a CLI and library for reading and safely editing structured JSON, TOML, YAML, dotenv, and INI documents.
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

//! Error types with context and helpful hints.

use std::fmt;
use std::io;

pub type DocumentResult<T> = Result<T, DocumentError>;

#[derive(Debug, Clone)]
pub enum DocumentError {
    EmptyPath,
    EmptyValues,
    UnknownSegment {
        path: String,
        segment: String,
    },
    UnregisteredArray {
        path: String,
    },
    SlugNotFound {
        prefix: String,
        slug: String,
    },
    SlugAlreadyExists {
        prefix: String,
        slug: String,
    },
    NotTraversable {
        path: String,
        got: String,
    },
    TypeMismatch {
        path: String,
        expected: String,
        got: String,
        hint: Option<String>,
    },
    PathNotFound {
        path: String,
    },
    IndexOutOfBounds {
        path: String,
        index: usize,
        len: usize,
    },
    ParseError {
        format: String,
        detail: String,
    },
    IoError {
        detail: String,
    },
    UnsupportedOperation {
        format: String,
        operation: String,
        detail: String,
    },
}

impl fmt::Display for DocumentError {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            DocumentError::EmptyPath => {
                write!(f, "empty path provided")
            }
            DocumentError::EmptyValues => {
                write!(f, "at least one value required")
            }
            DocumentError::UnknownSegment { path, segment } => {
                write!(f, "path `{}` segment `{}` not found", path, segment)
            }
            DocumentError::UnregisteredArray { path } => {
                write!(f, "array at `{}` not registered in KeyedList", path)
            }
            DocumentError::SlugNotFound { prefix, slug } => {
                write!(f, "no element with slug `{}` found in `{}`", slug, prefix)
            }
            DocumentError::SlugAlreadyExists { prefix, slug } => {
                write!(f, "slug `{}` already exists in `{}`", slug, prefix)
            }
            DocumentError::NotTraversable { path, got } => {
                write!(f, "path `{}` is {}, cannot traverse further", path, got)
            }
            DocumentError::TypeMismatch {
                path,
                expected,
                got,
                hint,
            } => {
                write!(f, "field `{}` expects {}, got `{}`", path, expected, got)?;
                if let Some(h) = hint {
                    write!(f, "\n  hint: {}", h)?;
                }
                Ok(())
            }
            DocumentError::PathNotFound { path } => {
                write!(f, "path `{}` not found in config", path)
            }
            DocumentError::IndexOutOfBounds { path, index, len } => {
                write!(
                    f,
                    "index {} out of bounds at `{}` (len {})",
                    index, path, len
                )
            }
            DocumentError::ParseError { format, detail } => {
                write!(f, "failed to parse {}: {}", format, detail)
            }
            DocumentError::IoError { detail } => {
                write!(f, "io error: {}", detail)
            }
            DocumentError::UnsupportedOperation {
                format,
                operation,
                detail,
            } => write!(f, "{} does not support {}: {}", format, operation, detail),
        }
    }
}

impl std::error::Error for DocumentError {}

impl DocumentError {
    /// Wrap a serde deserialization failure as a `TypeMismatch` so callers that
    /// do a read-modify-write cycle (set_path → serde round-trip) surface a
    /// consistent error style rather than a raw serde message.
    pub fn from_serde(path: impl Into<String>, err: impl std::fmt::Display) -> Self {
        let msg = err.to_string();
        // serde messages look like "invalid type: string \"x\", expected u16 at …"
        // Strip the trailing " at line N column M" to keep the hint concise.
        let hint = msg
            .split(" at line ")
            .next()
            .unwrap_or(&msg)
            .trim()
            .to_string();
        DocumentError::TypeMismatch {
            path: path.into(),
            expected: String::new(),
            got: hint,
            hint: None,
        }
    }
}

impl From<io::Error> for DocumentError {
    fn from(err: io::Error) -> Self {
        DocumentError::IoError {
            detail: err.to_string(),
        }
    }
}