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

Annotations already establish read-only, idempotent, non-destructive behavior, so the description's additional 'starts nothing and spends no credits' meaningfully reinforces cost and side-effect safety. It also clarifies that iter0 does not sell credits or take payment through ChatGPT, adding boundary context beyond annotations. It does not, however, describe return behavior or pagination, though the output schema and parameter descriptions cover those areas.

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 front-loaded with the action and usage trigger, followed by scope exclusions and cost/payment boundaries. It is dense but efficient; every sentence contributes a distinct constraint or clarification. A slightly shorter phrasing could improve scanability, but nothing is clearly redundant.

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?

Given the rich annotations, full schema description coverage, and an output schema, the description provides sufficient context: it explains what opens, when to use it, that it is read-only with no credit spend, and the topical boundaries. Nothing critical for correct invocation appears to be 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 description coverage is 100%: limit, query, and cursor are all explained in the schema, including defaults and constraints. The description adds no parameter-specific meaning beyond what the schema already provides, so the baseline score of 3 is appropriate.

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 uses a clear verb and resource: 'Open the person's iter0 projects' and then specifies the surface includes recent designs, search, and a new-website box. It distinguishes the tool from broader design/branding advice and hosting/domain topics, but it does not explicitly differentiate it from sibling tools such as iter0_list_my_designs, which could also be used to see a person's designs.

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 gives a clear usage trigger: 'Use when they ask to open iter0 or see their iter0 projects.' It also states several exclusions (general design advice, hosting elsewhere, domains, credit purchases), which helps prevent misuse. However, it does not name a specific alternative tool for overlapping requests, so the routing guidance is slightly incomplete.

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