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

With no annotations provided, the description carries the transparency burden. It discloses that the URL is short-lived and signed, that it points to the current source zip, that authentication is required, and that the platform rebuilds and auto-ships for owned-tier apps. It does not mention expiry duration or the exact return envelope, so it stops short of a 5.

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 compact despite conveying a multi-step workflow, and the main purpose is front-loaded. The embedded workflow is useful but slightly dense; every clause earns its place, though the final authentication sentence mostly restates what the schema already implies.

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 simple one-required-param tool with no output schema, the description covers purpose, workflow, authentication, and downstream steps. It omits the URL expiration timeframe and the exact response format, but the agent has enough context to invoke the tool correctly and interpret the result as a download URL.

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 50%: appName has no schema-level description, while sessionKey does. The description confirms appName is required and ties it to the target Osir app, but it does not explain how to obtain or format the app name or how sessionKey flows differ. The added semantic value is modest and only partially compensates for the missing appName schema description.

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: 'Get a short-lived signed download URL for an Osir app's current source zip.' It clearly distinguishes this from sibling tools like osirAppDeploy, osirAppCreateUpload, and osirAppStatus by stating it is for retrieving the source archive. The workflow reference makes its role unambiguous.

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 states when to use this tool: 'use this to make edits to a deployed app without the user re-attaching the project.' It also names the follow-up sibling tools (osirAppCreateUpload, osirAppDeploy) and the important constraint to deploy under the SAME name. This is actionable routing guidance.

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