fl_redo

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

Annotations already mark this as destructive and non-read-only, so the description's main added value is the phrase 'and verify it', which hints that the tool actively confirms the resulting history state. It does not explain guard-failure behavior or what exactly gets verified, though the output schema may cover the return shape.

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 sentence with no wasted words, front-loading the core action ('Move...') before the secondary verification detail. It avoids repeating the title or restating schema information.

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 two-optional-parameter tool with a rich schema, output schema, and safety-related annotations, the description is nearly sufficient. The main gap is the missing explicit relationship to fl_undo and guidance about when the guards should be supplied.

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 provides 100% coverage with detailed descriptions for expected_before and session_fingerprint, including their roles as guards. The description adds no parameter-specific semantics, which is acceptable because the schema already carries that burden.

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 concrete action ('Move to the next...') on a defined resource ('absolute undo-history position') and adds a verification step. It is less immediately transparent than 'redo the last undone change', but the title annotation and sibling fl_undo disambiguate the intent.

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 'next' qualifier implies this is the forward counterpart to fl_undo, so an agent can infer when to use it. However, the description never explicitly says 'use after fl_undo' or names alternatives, prerequisites, or conditions under which this tool should be preferred.

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