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

No annotations are provided, so the description carries the full burden. It usefully discloses that the live session TS is authoritative, that GeoJSON must not be reposted, that form-capable clients may be prompted in-band, and that legacy hosts return CLARIFICATION_REQUIRED. It never states that the two source territories are consumed/replaced or whether the merge is reversible — a notable gap for a mutation.

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?

Information is front-loaded (Tier tag, When, Prerequisites, Args, Next) and every clause carries signal, but the telegraphic jargon (TS, MC, TAL, MG-001..004) makes it hard for an agent without domain context to parse, and the scenario codes add little operational value.

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 no explanation, and the description does cover the main invocation paths. However, for a 16-parameter, annotation-free mutation, the unexplained rebalancing knobs (balance_tolerance, disruption_weight, repair_policy) leave the agent unable to fully control the operation.

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 16 parameters, so the description must compensate and only partially does. It explains map_session_id, source_tal_id, territory_id_a/b, ts_handle/ts, and hints at dwell_time, but leaves balance_tolerance, disruption_weight, repair_policy, part_layer, point_layer, visit_frequency_field, objective, and guidance_handle entirely undefined despite being central to the 'minimal disruption' claim.

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+resource: 'merge two adjacent territories and rebalance with minimal disruption', which implicitly separates it from territory_split and territory_rebalance. It does not name those siblings explicitly, so the agent must infer the boundary rather than being routed to the right tool.

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?

'When:' and 'Prerequisites: adjacent territory_id_a and territory_id_b in source TAL' give clear context, and it distinguishes the Open MC path from the Headless path. It stops short of explicit when-not conditions or naming console alternatives like territory_split/territory_rebalance.

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