Reads a file from permitted filesystem paths, returning its contents while enforcing path restrictions.
Reads a file from the allowed filesystem paths
| Name | Required | Description | Default |
|---|---|---|---|
| path | Yes | Path to the file to read |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, idempotentHint=true, and openWorldHint=false. The description adds the allowed-filesystem-paths constraint, but does not mention return format, encoding behavior, error cases, or size limits. This adds some useful context but leaves behavioral gaps.
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?
A single front-loaded sentence with no wasted wording. The core action and scope are stated immediately.
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 one-parameter read tool, the description is adequate to invoke it. However, with no output schema, it could clarify that the result is file contents, and it does not mention error behavior for missing or disallowed paths.
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?
The schema has 100% description coverage for the only parameter, path, so the schema already documents it. The description adds no syntax, relative-vs-absolute path, or permission details beyond what the schema provides. Baseline 3 is appropriate.
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?
States a specific verb and resource: 'Reads a file'. The 'allowed filesystem paths' scope is useful. It distinguishes reading from the sibling file_write, but does not explicitly differentiate from json_transform or echo.
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?
Usage is implied by the read operation and the allowed-path constraint, but the description gives no explicit when-to-use guidance, no when-not-to-use guidance, and no comparison with siblings such as file_write.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.