diff_vault

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the burden and does reasonably well: it declares the read-only nature via 'Show', explains the unified diff convention ('-' removed, '+' added), and discloses the return shape as {diff} or {error}. It stops short of describing failure conditions (e.g., invalid commit hash, missing path or binary/large diffs), which would have made this a 5 for an unannotated tool.

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?

Three short sentences, front-loaded with purpose, then the diff-reading convention, then the prerequisite and return shape. Every sentence carries information the agent needs, with no filler or repetition of the tool name.

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 two-parameter read tool with no annotations and no output schema, the description covers purpose, workflow prerequisite, output format convention, and return shape ({diff} or {error}). The remaining gap is the exact expected form of the 'path' argument and error conditions, which is minor but non-trivial.

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 coverage is 0%, so both parameters rely on the description. The description does add meaning for 'commit' by calling it a commit hash sourced from history_vault, and 'path' is implied to be the node path by 'change one commit made to a node'. However, it never states the expected format of 'path' (vault-relative? node ID?), leaving half the parameter semantics to inference.

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 opens with a specific verb and resource: 'Show the change one commit made to a node', which is clearly distinct from list/history style siblings. The phrase 'as a unified diff' further defines the output form. What keeps it from a 5 is that it doesn't explicitly contrast itself with siblings like read_vault or history_vault, though it does route the agent to history_vault for the commit hash.

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?

It gives a concrete workflow prerequisite – 'Get the commit hash from history_vault' – which tells the agent how to obtain the required input before calling. It does not state when to prefer this over read_vault or history_vault, and gives no exclusion conditions, so it's clear context without full when-not guidance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.