Copy a file up to 8 MiB with SHA-256 verification, ensuring no overwrites, and return a recoverable change ID.
Copy one regular file <=8 MiB within an rw workspace. Require source SHA-256 and an absent destination with an existing parent. No recursive trees, links or overwrite. Returns a recoverable change_id.
| Name | Required | Description | Default |
|---|---|---|---|
| path | Yes | ||
| workspace | Yes | ||
| request_id | Yes | ||
| destination | Yes | ||
| expected_sha256 | Yes |
Changes observed during successful MCP inspections.
v0.3.2-demo.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare destructiveHint=true and idempotentHint=true. The description adds valuable behavioral specifics: size limit, prohibition on links/overwrite, and the return of a recoverable change_id. These go beyond the annotations and clarify the operation's side effects and constraints.
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, no filler. The first sentence front-loads the core action and constraint, the second adds prerequisites and return behavior. Every clause earns its place with zero redundancy.
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?
While the description covers key constraints and return info, it omits any explanation of request_id, which is a required parameter. There is no output schema, so the description should clarify all parameters. The omission of request_id and lack of explicit per-parameter guidance leaves the tool less complete than ideal for a 5-parameter operation.
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 must compensate. It indirectly explains expected_sha256 (source SHA-256), destination (absent with existing parent), and workspace (rw workspace), but does not explicitly define request_id or clarify the relationship between path and workspace. The coverage is partial and leaves some parameters underspecified.
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 specific verb (copy), resource (one regular file <=8 MiB), and scope (within an rw workspace). It clearly distinguishes from siblings like move_file (copy vs move) and delete_file, and adds constraints that define its domain. This is unambiguous and highly discriminative.
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 description gives prerequisites (source SHA-256, absent destination with existing parent) and exclusions (no recursive trees, links, overwrite), but it does not explicitly name alternatives or state when to prefer this over move_file or write_file. The usage context is implied rather than explicit.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.