firefox_tab_history

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

Annotations already declare readOnlyHint=false, destructiveHint=true, openWorldHint=true and idempotentHint=false, so the mutation and risk profile is known. The description adds real context beyond that: 'Navigation protection blocks unauthorized destinations,' which tells the agent the action can be refused for policy reasons. However, it never says what a block looks like (error vs no-op), nor that going back may discard forward history.

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 short sentences with the action front-loaded and the constraint second; no filler or repetition. It is arguably too terse for a mutating navigation tool, but nothing written is wasted.

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 destructive, non-idempotent navigation tool with no output schema and zero parameter documentation, the description should explain the blocked-destination failure mode and the effect on existing tab state. It flags the protection mechanism but leaves the agent guessing about outcomes and prerequisites such as holding the tab.

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 description coverage is 0%, so the description is the only place parameter meaning could be added, and it largely isn't. 'Authorized tab' loosely implies tabId must reference a tab the agent has acquired, but nothing is said about direction beyond what the enum already conveys.

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 pair and resource: go back or forward within a tab. This distinguishes it from firefox_navigate (go to a URL) and firefox_history (browsing history listing) without needing to open a schema, though the description never names those siblings explicitly.

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?

There is no explicit when-to-use guidance and no exclusions or alternatives. An agent must infer that this is for session history traversal rather than URL navigation, and nothing says when to prefer it over firefox_navigate or firefox_history. The only usage constraint given is the vague 'authorized tab' phrase.

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