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

Beyond the annotations (readOnlyHint=false, destructiveHint=false, non-idempotent, closed-world), the description discloses the plan-then-verify-then-execute pipeline and the dry-run escape hatch, which is genuinely useful behavioral context. It doesn't say whether a new file is produced or the source is modified, nor what happens when the instruction can't be fulfilled.

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 tight sentences: the first leads with a concrete example of the instruction, the second explains the plan/execute model and the dry-run flag. No filler.

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?

With an output schema and annotations present, the description needs only to explain the planning/execution model and dry-run behavior, which it does. It could still clarify output vs. in-place mutation and the failure mode for unsupported instructions.

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 already high (83%), and the description adds real meaning to the two most important inputs: 'instruction' is natural language describing the desired change (with an example), and 'run=false' returns only the plan. The file-source parameters are left entirely to the schema.

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 concrete verb (edit), resource (PDF), and a distinctive mechanism: natural-language instruction turned into a checked plan of FynePDF actions that is then executed. The example instruction makes the tool's scope tangible. It does not explicitly distinguish itself from 'edit_pages' or 'redact_pdf', so it stops short of a 5.

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 clear operating context: describe the change in plain language and the tool plans then runs it, with 'run false' acting as a documented dry-run/preview mode. No alternatives (e.g. edit_pages for structured operations) are named, so there is no exclusion guidance.

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