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

Annotations already declare readOnly, idempotent, non-destructive, so the safety profile is covered. The description adds meaningful behavior beyond that: it returns canonical state plus permitted actions (routing-relevant), and explicitly states it does not open another session, clarifying that no side effects occur.

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?

Two sentences, zero waste. The return contents are front-loaded and the usage triggers and non-side-effect note follow immediately; nothing needs trimming or reordering.

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-value structure need not be spelled out, and the description still summarizes what comes back (state, offer version, guidance, permitted actions). Combined with the when-to-use triggers and no-side-effect note, the definition is complete enough for the agent to call it correctly.

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 (session_id) with 100% schema description coverage, so the schema fully documents the input. The description says 'existing negotiation' which confirms it must reference a prior session, but adds no format or syntax detail beyond the schema. 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?

Specific verb ('Read') plus resource ('negotiation'), and it enumerates what is returned: canonical state, current offer version, guidance and permitted actions. It also distinguishes itself from siblings by stating 'this does not open another session,' clearly separating it from haggl_start_negotiation.

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?

Gives concrete when-to-use triggers ('after human changes, reloads, transport switches or uncertain results') that tell the agent this is a refresh/re-sync call. It does not name specific alternative sibling tools for those scenarios, but the context is unambiguous.

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