Wait for a browser download matching a URL or filename pattern to finish, allowing agents to proceed only when the file is ready.
Wait for a download matching a URL/filename pattern to finish
| Name | Required | Description | Default |
|---|---|---|---|
| tab | No | ||
| pattern | Yes | ||
| profile | No | Browser ID from sleeper_sessions; optional with one connected browser. | |
| timeout_ms | No |
Changes observed during successful MCP inspections.
v2.0.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden, yet it only says the wait ends when the download 'finishes'. It does not disclose what happens on timeout, whether partial downloads count, whether it blocks or errors, or any permission/session requirements.
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?
One front-loaded sentence with no filler or redundancy, so every word earns its place. The terseness is arguably under-specification rather than padding, which is penalized under contextual completeness instead.
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?
A blocking wait tool with four parameters, no annotations, no output schema, and unspecified timeout/error semantics needs considerably more description. An agent cannot know how long it will block, how to set timeout_ms, or what a failed wait 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 coverage is only 25% (just 'profile'), leaving tab and timeout_ms undocumented anywhere. The description adds meaning only for the required 'pattern' argument ('URL/filename pattern'), which the schema leaves bare, but does not compensate for the other undocumented parameters.
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 specific verb (wait), resource (download), and matching criterion (URL/filename pattern). It is clearly distinguishable from sibling wait tools like sleeper_wait_url, sleeper_wait_xhr, and sleeper_wait_dialog, though it doesn't name any of them explicitly.
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?
Nothing states when this tool should be preferred over the many other wait siblings (sleeper_wait, sleeper_wait_url, sleeper_wait_xhr, etc.), nor what prerequisite (a triggered download) is needed. Usage can only be inferred from the tool name.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.