mcp_index_scan

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

No annotations are provided, so the description must carry full burden. It does not disclose whether the scan is read-only or idempotent, nor any side effects like overwriting an existing index. This is insufficient for a tool that modifies state (indexing).

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 clearly state purpose and default behavior with no wasted words. Front-loaded with the core action, followed by a key optimization detail.

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?

Given low complexity (2 optional parameters, no output schema), the description is nearly complete. It covers the tool's main function and a configuration note, but lacks a note about whether the scan is incremental or full rebuild.

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% with descriptions for both parameters. The description adds no extra meaning beyond the schema, matching the baseline expectation. The default behavior note echoes config_filter's default value.

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 'Scan all MCP servers and index their tools' with a specific verb and resource, distinguishing it from sibling tools like mcp_index_search. However, it could more explicitly contrast with rebuild or search tools.

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 provides a default behavior note ('By default, scans only configured servers') and mentions token savings, which guides usage. But it lacks explicit when-to-use or when-not-to-use compared to siblings like mcp_index_rebuild or mcp_index_search.

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