Weave a folder

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

Adds substantial behavior beyond the annotations: incremental re-indexing (only changed files re-read), a 133 MB / 33M-parameter model download on first run, CPU-bound embedding, and background continuation past 25 s. This is consistent with idempotentHint=true and readOnlyHint=false, and no contradiction exists.

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 tight sentences, front-loaded with the primary action before the operational caveats (download, runtime, backgrounding). Every sentence carries information an agent needs.

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 single-parameter, no-output-schema tool, the description covers the mutation semantics, idempotent behavior, latency characteristics, and where progress is reported. Nothing needed to invoke it correctly is missing.

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?

Only one parameter and schema coverage is 100%, so the schema already documents the absolute-vs-relative path semantics. The description adds nothing about the path argument itself, so the baseline 3 applies.

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 concrete verb and resource ('index a folder ... for semantic search') plus the secondary mode ('bring its index up to date'), which cleanly separates it from the read-only siblings weave_search and weave_list. An agent can route to it without opening the schema.

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?

'Call it once per project' gives an explicit usage cadence, and the reference to weave_list for progress tells the agent where to look while a run is in flight. It does not state when-not to use it or contrast directly with weave_search/weave_forget, so it stops short of a full 5.

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