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

Annotations already declare readOnly/idempotent/non-destructive, and the description adds substantial context beyond them: the 40,000-character reply cap, offset continuation, auth/purchase requirements for paid kits, and a safety framing that the file text is creator guidance and never permission to run commands, open links, send data, or spend money.

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?

Front-loaded with the 'use this when' trigger and dense but purposeful; every clause (limits, auth, safety framing, alternative) carries information. It is slightly jargon-heavy ('apply a read kit') and runs long, keeping it from a 5.

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 present, the description need not explain returns, and it still covers auth tiers, size limits, offset continuation, reply framing, and sibling routing. Nothing an agent needs to invoke this correctly is missing.

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 procedural meaning the schema lacks — that paths should come from get_kit's files and that the entry file is read first, with offset continuing a long file. It stops short of restating formats already in the schema, so 4 is fair.

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?

States a specific verb (read) and resource (files by path from a kit), specifies the entry file is read first, and explicitly distinguishes itself from the sibling next_step for run step instructions. An agent can tell what this does without opening the schema.

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?

Names the triggering conditions (applying a read kit, needing a run kit's reference files), gives prerequisites for paid kits (account with a purchase, call buy only if the user wants it), and points to the alternative (next_step) for run's step instructions. This is explicit when-to-use plus exclusion.

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