infosys_index

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

Adds substantial context beyond annotations: incremental fetching (only new/changed pages via sitemap lastmod), what is extracted (title/kind/library/declaration), and a concrete cost estimate (300 pages ≈ 30-60 s). One minor tension: it writes to a local cache while readOnlyHint=true, though cache population is idempotent and non-destructive so it does not rise to a true contradiction.

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?

Three sentences, verb-first, no filler. The example glob, timing estimate, and prerequisite each earn their place and are ordered by usefulness.

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 explained, and the prerequisite/enablement story is complete. The gap is the undocumented force/max_pages parameters, which an agent cannot disambiguate from the description.

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 0% and there are 3 params, so the description must compensate. It explains 'book' well (including glob syntax), but 'force' and 'max_pages' are left entirely undocumented in both schema and description, leaving two of three parameters ambiguous.

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+resource ('Index a book (or glob of books)') with a concrete example glob ('tcplclib_tc3_*') and names the target (the local cache). An agent immediately knows this builds a searchable index and can distinguish it from the infosys_* search siblings.

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?

Explicitly states the prerequisite: 'Needed before infosys_search_symbols/search_code can see a library' and the fallback behavior ('infosys_search falls back to the web'). This names the dependent siblings and the when-to-use condition precisely.

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