Loads an image file from the shell so you can view its contents directly. Use the thread_id from Initialize when available to maintain context.
Read an image from the shell. Use the thread_id returned by Initialize when available; legacy clients may omit it.
| Name | Required | Description | Default |
|---|---|---|---|
| file_path | Yes | ||
| thread_id | No |
Changes observed during successful MCP inspections.
v5.6.6Input schema / properties / thread_idAdded value: +{
+ "default": "",
+ "type": "string"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true and openWorldHint=false, and the description does not contradict them. The added note about thread_id and legacy clients is useful behavioral context beyond the structured fields, but the description does not disclose other behaviors such as error cases or what happens when the image cannot be read.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two sentences with no filler. The primary action is front-loaded, and the optional parameter guidance is placed in the second sentence where it belongs.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a simple read-only tool with minimal schema, the description covers the main input and the key optional parameter. Still, it lacks an explicit distinction from ReadFiles and does not mention what the tool returns, which would help an agent use it more reliably.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 0%, so the description carries the burden of explaining parameters. It adds meaningful semantics for thread_id ('returned by Initialize... legacy clients may omit it'), but it says nothing about file_path beyond the schema's name and type.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states a clear action ('Read an image') and a resource/context ('from the shell'), so an agent can generally tell what the tool does. However, it does not explicitly distinguish ReadImage from the sibling ReadFiles, leaving some ambiguity about when the image-specific tool is preferred.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The only guidance is about the thread_id parameter: use the one from Initialize when available, and legacy clients may omit it. There is no guidance about when to use ReadImage versus alternatives like ReadFiles or BashCommand, so tool-selection context is missing.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.