ecg_stats

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

With no annotations, the description carries the full burden, but it does disclose the key traits: the operation is read-only and fact bodies are excluded from the response, so an agent knows no content is returned. It omits permissions requirements, session-state prerequisites, and whether counts are eventually consistent.

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, front-loaded with the operation's nature and followed by the exact metric list. The metric enumeration is dense but each item earns its place by defining the return payload; nothing is padded.

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?

There is no output schema, but the description enumerates the returned counts (exchanges, active/superseded/total facts, edges, entities, open conflicts) and states what is excluded, which is the information an agent needs. The only real gap is the undefined session_id.

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% and session_id is undocumented in both schema and description, so the description does not compensate for the gap. However, with a single self-evident identifier parameter, the practical risk is low, putting this near the baseline rather than below it.

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 names a specific verb+resource ('Read-only counts for the session's repository') and enumerates exactly which metrics are returned, which distinguishes it from diagnostic siblings like ecg_list_conflicts and ecg_search_context. It stops short of explicitly naming an alternative sibling, so it is clear but not fully differentiated.

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 statement of when to call this versus siblings — e.g. whether it replaces or complements ecg_list_conflicts for conflict counts, or whether the session must be committed first. Usage is only inferable from the metric list; no conditions or exclusions are given.

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