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

With no annotations, the description carries the full burden and largely delivers: idempotency per user_id, dual-surface rendering behavior (chat ui:// vs. browser tab for Cursor), and the guarantee that map_url is always returned. These are non-obvious operational traits an agent would otherwise guess wrong.

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 tier label and the primary action, then organized into When/Prerequisites/Next/Scenarios blocks. Dense but each clause carries operational meaning; slightly over-packed with jargon (I-1, MC-000, S004) that adds little for tool selection.

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 needn't be described, and the description covers workflow sequencing, the dual surface, and idempotency. Given 11 undocumented params, some input semantics remain thin, but an agent can call it correctly for the primary flows.

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 11 params, so the description must compensate. It explains new_project, presentation.view_name (with enum values), presentation.debug_panel, mode (as a driver of view defaults), and alludes to ts/ts_handle/job_id as inputs, but leaves expiry_seconds, guidance_handle, active_tal_id, interaction_flags, and user_id undocumented.

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 (open/reuse the map visualization) and its position as the 'FIRST step of non-headless territory work'. It clearly delineates the two use cases (blank planning map vs. reuse an existing TS/job map), letting an agent distinguish it from siblings like ensure_map_viewer and set_map_state.

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:' clause names both entry conditions, gives the new_project=true vs. omitted behavior for reuse, and states prerequisites and the next step (hand user map_url, then ensure_map_viewer until viewer_status.connected). It also gives an explicit when-not: 'Do not open a second surface or call this tool again to fix a map.'

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