Apply to YC job (human-in-loop)

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

With no annotations, the description carries the burden and does well: it reveals the default dry-run behavior, the human-approved second call, the resume location prerequisite, and the no-browser mode. Minor gap: the approval email recipient is called APPROVAL_EMAIL here but NOTIFY_TO in the schema, and there's no statement about the outcome/return after real submission.

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?

Three sentences, front-loaded and compact; each sentence adds a distinct piece of workflow knowledge. The only minor flaw is the email-recipient name inconsistency, which doesn't affect structure.

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?

Despite 16 parameters and no output schema, the description covers the critical workflow, prerequisites, and modality. It doesn't mention how to obtain companyId/jobId (though schema covers those) and omits the post-submit response/return, leaving slight ambiguity for an agent about what success looks like.

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 the baseline is 3; the description adds workflow-level context around dryRun but doesn't add per-parameter meaning beyond what the schema already provides.

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 opens with a specific verb and resource – 'Apply to a YC job' – and immediately adds the per-startup customized cover message. The human-in-loop workflow and API-only scope further distinguish it from sibling search/list/get/fetch tools, so an agent can select it without confusion.

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 lays out the exact sequence: default dryRun=true sends approval email and does not submit, then after APPROVE re-call with dryRun=false. It also sets the constraint that the resume must be in ./resumes/ and that it is API-only, no browser, but it does not explicitly say 'use yc_search_jobs first' or name alternatives.

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