Struct JsonObject 

pub struct JsonObject { /* private fields */ }

A JSON object, validated on construction.

Implementations

impl JsonObject

pub fn new(text: impl Into<String>) -> Result<Self, JsonObjectError>

Validates text as a JSON object.

Errors

JsonObjectError::InvalidJson when the text is not well-formed JSON, and JsonObjectError::NotAnObject when it parses but is not an object — an array or a bare scalar is a different thing, and 2025-06-18 structuredContent is specifically an object.

Examples

use protocol_droid::domain::ir::JsonObject;

let json = JsonObject::new(r#"{"temperature": 0.7}"#)?;
assert_eq!(json.as_str(), r#"{"temperature": 0.7}"#);

pub fn as_str(&self) -> &str

The text, exactly as it was validated.

pub fn from_value(value: Value) -> Result<Self, JsonObjectError>

Validates a serde_json::Value and stores it.

A tool handler’s result is built from data — the argument echoed back, a computed value, an error message composed from a failure. Doing that with new means format!ing a JSON document by hand, and a handler that interpolates a peer’s string into a JSON literal without escaping it is an injection bug. This is the constructor that makes that mistake unavailable.

The value is serialised rather than kept, so a JsonObject is still one validated String and still owns no borrowed peer’s data.

Errors

JsonObjectError::NotAnObject when the value is not an object. JsonObjectError::InvalidJson when the value cannot be serialised, which for a Value cannot happen — but the error type is the honest one, and inventing a second error for an unreachable case would be a promise this function cannot keep.

Examples

use protocol_droid::domain::ir::JsonObject;

let value = serde_json::json!({ "echoed": "quotes \" and \\ survive" });
let json = JsonObject::from_value(value)?;
assert_eq!(json.as_str(), r#"{"echoed":"quotes \" and \\ survive"}"#);

pub fn into_string(self) -> String

Consumes the object, yielding its text.

Trait Implementations

impl Clone for JsonObject

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for JsonObject

fn fmt(&self, formatter: &mut Formatter<'_>) -> Result

Prints the text, since a JsonObject has no other meaningful state and the text is what a caller debugging a lossless round trip needs to see.

impl Default for JsonObject

fn default() -> Self

The empty object, {}.

A tool handler returns a JsonObject and cannot return a Result, because MCP reports a tool failure as a successful call carrying isError: true. So a handler that cannot build the result it meant to build needs somewhere to fall back to, and it needs to be infallible. {} is that place: it is a valid document under every revision of the protocol, so no fallback can itself be a parse error.

Not "", which is the default a String-backed type reaches for and which is not a JSON object at all.

impl Display for JsonObject

fn fmt(&self, formatter: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for JsonObject

impl Hash for JsonObject

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for JsonObject

fn cmp(&self, other: &Self) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

fn clamp_to<R>(self, range: R) -> Self

where Self: Sized, R: ClampBounds<Self>,

🔬This is a nightly-only experimental API. (clamp_to)

Restrict a value to a certain range.

impl PartialEq for JsonObject

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl PartialOrd for JsonObject

fn partial_cmp(&self, other: &Self) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl StructuralPartialEq for JsonObject