Search inside scanned pages

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

The description discloses several important behaviors beyond annotations: 'total' counts documents, not occurrences; the index reports no page number so matches never give a leaf; inside_container behavior is explained (container vs matched_file); and it advises following source_url to locate a passage. These are non-obvious behavioral traits that annotations (readOnly, idempotent) don't cover.

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 dense but well-organized: it opens with purpose, then explains search behavior, output caveats, container disambiguation, and finally alternatives. Every sentence adds unique information; no filler or repetition.

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 5 parameters, an output schema, rich annotations, and multiple sibling tools, the description covers all critical aspects: query syntax, pagination, output semantics, edge cases (inside_container), and when to use alternatives. The output schema handles return value details, so no additional description is needed.

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?

Since schema coverage is 100%, baseline is 3. The description adds value by explaining how to use the query parameter ('Put a phrase in double quotes...'), how pagination works ('ask for page 2, 3 and so on'), and clarifies output semantics like 'total' is not a term frequency count. This supplements the schema without duplicating it.

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 clearly states 'Search the text inside digitised books, newspapers and documents on the Internet Archive' with a specific verb, resource, and scope. It also explicitly distinguishes from search_items and search_books when looking for works by title/author/subject, making sibling differentiation strong.

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 explicitly states when to use this tool (to find text inside scanned pages) and provides an explicit exclusion: 'Use search_items or search_books instead when looking for a work by its title, author or subject.' Also gives practical tips on quoted phrases and pagination, which helps agents decide the correct invocation.

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