knowledge_index_directory

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

With no annotations, the description must disclose behavioral traits. It states 'index or update' and lists supported file types, but does not clarify destructive behavior (e.g., overwrite vs incremental), side effects, permissions, or whether it checks for existing indexes. Minimal transparency.

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 sentences: first states the purpose, second lists supported formats. No redundant words, front-loaded with the key action. Every sentence earns its place.

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?

The description is adequate but leaves questions: what happens if the directory already has an index? How does force_reindex interact? The presence of an output schema reduces the need to explain return values, but the description does not differentiate from knowledge_refresh_index or explain recursion behavior beyond the schema.

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 100%, so parameters are well-documented in the schema. The description adds value by listing supported file types, which is not in the schema. While it doesn't elaborate on each parameter, the extra context justifies a slight boost above the baseline of 3.

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 the tool indexes or updates a knowledge directory for semantic search, listing supported file types (.md, .py, .ipynb). This specific verb+resource+scope distinguishes it from sibling tools like knowledge_refresh_index or knowledge_drop_index.

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?

The description implies usage for indexing or updating directories but lacks explicit guidance on when to use this tool versus alternatives (e.g., knowledge_refresh_index). No exclusions or context about prerequisites are provided.

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