source_page

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

Annotations already declare readOnly/non-destructive/openWorld=false, so the description adds value with what's beyond them: page read is gated on source hash validation, image return is optional, and the tool explicitly does not certify interpretation. It omits what happens on a hash mismatch or whether text is returned alongside the image.

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?

Two dense sentences, front-loaded with the action and its precondition, followed by use cases and exclusions. No filler and nothing restated from the schema or annotations.

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?

With no output schema and zero schema descriptions, the description covers the core contract: page numbering, hash validation, optional image. Remaining gaps are paper_id semantics and failure behavior on validation error, which matter for a lookup that can fail.

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 parameter meaning. It does this well for `page` (1-based, original PDF numbering, which is a real correctness detail), and implies `render` via "optionally return its image," but leaves `paper_id` completely unexplained and never states the render default of true.

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?

States a specific verb and resource (read an ORIGINAL PDF page) with meaningful scope qualifiers: 1-based indexing and source-hash validation. It is unmistakably distinct from list_papers/search/fetch, though it never names a sibling to contrast against 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?

Gives concrete positive triggers (table column alignment, footnotes, figures, formulas, missing experimental conditions) and an explicit exclusion (does not fetch external supplements, does not certify interpretation). It stops short of naming which sibling to use instead when the need is, e.g., a supplement or a search.

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