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

The annotations already cover read/write and destructiveness, and the description adds useful behavioral context: no compute starts yet, a job is reserved, the deck must be uploaded before start_job, and the deck must be a .tar.gz <= 2 GB. It does not discuss cleanup if the upload never happens, but that is a minor gap given the 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?

The description is two sentences, front-loads the step/context, and contains no filler. Every clause either defines the tool's output, imposes a constraint, or gives the next action.

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 7-parameter tool with no output schema, the description covers the workflow well and the schema documents all parameters. The main omission is explicit mention of the returned job id and its role in the start_job call; the phrase 'reserves a job id' implies it, but a more explicit handoff would make the sequence fully self-contained.

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. The description adds value beyond the schema by specifying the upload format and constraints (.tar.gz, <= 2 GB, relative paths, `input` at `input`), which clarifies how parameters like `input` are used in practice.

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 and resource: validate the spec, reserve a job id, and return a presigned upload_url. It also names the subsequent step (start_job), so the tool's role in the two-step big-deck flow is unmistakable and clearly distinguished from 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?

The description explicitly says this is 'Step 1 of the two-step path for big decks' and gives the exact sequence: PUT the deck to upload_url, then call start_job. It does not explicitly rule out alternative one-step flows like submit_job, but the workflow context is strong.

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