kb_set_location

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

Goes well beyond the annotations (readOnlyHint=false, idempotentHint=true, destructiveHint=false) by listing the full validation gauntlet (not a file/drive root, local fixed drive, no network/USB/cloud-sync paths, writable, >=1 GB free), the fail-safe 'nothing is changed', the guarantee that an existing database is never moved or deleted, and the readonly-mode refusal plus auditing. This is consistent with destructiveHint=false.

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?

Front-loaded with the action and its primary constraint, and the validation list is compact. The heavy parenthetical packing and the internal reference 'N127' add density that a cold agent cannot decode.

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?

For a two-optional-parameter mutation tool with an output schema available, everything an agent needs is present: usage gating, validation rules, failure semantics, mutation safety, and the no-arg read behavior. Return values need not be described since an output schema exists.

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 the parameter meaning — and it largely does: it explains path constraints in detail and defines use_fallback's target directory, its prerequisite (user agreement), and mutual exclusion with path. It is somewhat dense and run-on, but the semantics are meaningfully richer than the bare schema.

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 — choose the folder for the knowledge database — and also discloses the no-argument read behavior (returns current location). No sibling tool performs this action, so an agent can distinguish it from kb_status, kb_reindex, or kb_rebuild without opening schemas.

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 constrains invocation: use ONLY a path the user provided, or use_fallback=true after the user agreed to D:\TwinCAT-MCP\knowledge, and 'not both'. This is a genuine when/how condition rather than an implied usage.

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