extract_pagesFree. Keep only the pages you name from a PDF, in the order you name them. Keep only the pages named in pages (1-based, like 2,5-9, repeats and any order allowed) from artifact_id. Returns the new artifact_id and a download_url (a link that works for about an hour).
| Name | Required | Description | Default |
|---|---|---|---|
| pages | Yes | ||
| artifact_id | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
Input schema / examplesAdded value: +[
+ {
+ "artifact_id": "99999999-aaaa-bbbb-cccc-dddddddddddd",
+ "pages": "1-3"
+ }
+]Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare it is a non-read-only, non-destructive, non-idempotent operation, so the bar is lower; the description still adds real value by noting it is free, that the output is a NEW artifact (source untouched), and that the download_url expires in about an hour. It does not cover failure modes for out-of-range page numbers.
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 cost and the core operation, and it is compact. There is mild redundancy between 'Keep only the pages you name' and 'Keep only the pages named in pages', but nothing bloated.
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?
An output schema exists, so return values need not be spelled out, yet the description helpfully summarizes them anyway. For a 2-param tool with 0% schema coverage, the format rules, ordering guarantee, cost, and link expiry make it complete enough to call correctly.
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 0%, so the description must carry the load, and it does for pages: 1-based indexing, the '2,5-9' syntax, allowed repeats and arbitrary order. artifact_id is only implied to be the source PDF, which is a minor gap, but the ambiguous parameter is well covered.
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+resource: it extracts a named subset of pages from a PDF and preserves the caller's ordering. It is clearly distinguishable in effect from siblings like delete_pages, reorder_pages, and rotate_pages, though it never names an alternative 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?
Usage is only implied: 'Free' signals it costs nothing and the page-selection semantics suggest when it applies, but there is no statement of when to prefer this over delete_pages, reorder_pages, or inspect_pdf, and no prerequisites or exclusions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
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