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

Annotations declare a non-read-only, open-world, non-destructive creation, and the description goes well beyond that: it discloses the returned slug + claim_token handshake required by add_screenshot/add_note, the save_url flow requiring a signed-in human, and the 30-day anonymous auto-deletion policy. That is exactly the behavioral context annotations cannot carry.

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 action and its handle, then the use cases, then the return contract and lifecycle caveat. Slightly dense with multiple clauses and em-dashes, but every sentence (including the 30-day expiry) earns its place.

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?

There is no output schema, so the description must carry the return contract — and it names review slug, claim_token, review_url, and save_url along with how each is used. Combined with the retention rule, an agent has everything needed to create, fill, and hand off the review.

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 description coverage is 100%, so title, summary, and product_url are already fully documented in the schema; the description adds no per-parameter syntax or format guidance. Baseline 3 applies because the structured field does the heavy lifting here.

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 and resource — 'Start a new Cobalt Capture review and get a handle for filling it in' — and contrasts the tool against the add_screenshot/add_note siblings that consume its output. An agent can distinguish this creation tool from update_review, get_review, and the append tools without opening a 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?

Explicitly frames the when: compile findings from a usability pass, pricing teardown, positioning audit, or QA run into one report. It also routes the agent around a real constraint — 'with no browser, add_screenshot(page_url=...) renders the pages for you' — naming the sibling to use in that situation.

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