Social Set Active Session

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states that it changes the active session for subsequent tools, but does not mention prerequisites (e.g., an existing session), reversibility, error conditions, or whether the change persists. For a state-changing tool, this is minimal and insufficient.

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?

The description is one concise sentence that front-loads the core action and effect. It contains no filler or redundant information, making it appropriately sized and efficient.

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 simple setter with a single parameter and no annotations, the description covers the key aspects: what it does (chooses account), the scope (subsequent authenticated tools), and implicitly how to get the username (from social_list_sessions). The presence of an output schema likely covers return details, so nothing critical is missing.

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?

The schema already fully documents the single 'username' parameter with a description pointing to social_list_sessions, achieving 100% coverage. The description adds marginal context by clarifying that it refers to a logged-in account, but does not meaningfully enhance schema semantics. Baseline 3 is appropriate.

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?

The description clearly states the verb 'choose' and the resource 'active session', explaining that it selects which logged-in account subsequent authenticated tools act as. This distinguishes it from siblings like social_list_sessions (which lists sessions) and social_connect_session (which establishes a connection), leaving no ambiguity about its role.

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?

The description implies that this tool should be used after listing sessions (since the username comes from social_list_sessions) and that it affects subsequent authenticated tools. However, it does not explicitly mention alternatives or when not to use it, leaving some inference required. It gives clear context but no exclusions or direct comparison to siblings.

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