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

With no annotations, the description carries the full burden and does a solid job: it discloses legacy auto-mapping behavior, the default duplicate_part_policy=keep_first, upload-handle provenance (aup_...), and prerequisites (part_layer chosen, viewer connected). It does not, however, state mutation semantics such as what existing territories are replaced or why expected_revision matters (optimistic concurrency), leaving a gap for a write operation.

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 'When:' trigger, followed by preconditions, exclusions, next steps, and scenario codes. Dense but each clause carries routing value; the scenario/Tier/MC references add mild clutter without much agent-facing benefit.

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 described. The gap is on the input side: for a 13-parameter mutation with zero schema descriptions, the definition leaves several parameters and the assignments-vs-handle distinction unexplained, so it is not fully complete for correct invocation.

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% across 13 parameters, so the description must compensate and only partially does: it clarifies assignments_handle format/origin, part_layer, ts/ts_handle optionality, and duplicate_part_policy. Several parameters remain undocumented (repair_policy, missing_part_policy, expected_revision, map_session_id, guidance_handle, the assignments array, tal_id/tal_label), and the relationship between the assignments array and assignments_handle is never explained.

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 action with scope: building a TAL from explicit part-to-territory assignments, tagged as the 'Known Assignments Builder'. It immediately distinguishes itself from siblings like ingest_accounts, auto_build, and account_build by naming each and the condition that selects them.

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?

Explicit when-to-use (user has explicit part-to-territory assignments, spreadsheet/legacy/hierarchical) plus three explicit 'Not for X—use Y' exclusions naming the correct alternatives. Prerequisites and follow-on steps are also stated.

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