Read a document's history

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

Annotations already establish readOnlyHint=true and openWorldHint=false, but the description adds substantial context beyond them: it explains the empty-list sidecar condition ('nothing can be reverted'), the meaning of `offset` as a selector for `geml_revert`, and the exact return form in each mode. This is well beyond the safety profile already covered by annotations.

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, front-loaded by mode, with caps-scanning labels ('WITHOUT `rev`' / 'WITH `rev`'). Every clause carries required information: mode behavior, selector semantics, and empty-list edge case.

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?

No output schema exists, so the description carries the return-shape burden, and it does: list mode returns revision entries with `offset` fields, single-revision mode returns full text. Annotations cover safety, and the description covers modes, edge cases, and the sibling-tool linkage, leaving no critical gap for a 2-param read tool.

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 100%, so the baseline is 3, but the description adds cross-tool meaning: it tells the agent that each listed revision's `offset` is what `geml_revert` accepts as `rev`, and that `-1` is the revision before the current one. That goes beyond the schema's self-contained parameter docs, though the schema already covers most syntax details.

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 gives a specific verb and resource ('Read a document's recorded history') and immediately separates the two operating modes, list vs. single revision. It also names the sibling `geml_revert` to clarify the relationship, so an agent can distinguish this read-only inspection tool from its siblings.

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 explicitly states when to omit `rev` (to list every revision newest-first) and when to supply it (to read one revision's full text). It further clarifies the boundary with `geml_revert` by noting this is 'for reading ... without restoring it,' giving a clear when/when-not signal.

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